John Leganski


“John Leganski is the rare talent in Washington who combines great vision for what’s possible with relentless commitment to the job at-hand. His ready insights were of immense value to myself and the entire House Republican Leadership team…Simply put, John’s understanding of the current political landscape and the people who shape it is second to none.”
  • Former Deputy Chief of Staff to the Speaker of the House
  • Over a decade of experience in congressional policymaking, vote counting, and floor procedure with a focus on tax, financial services, technology, appropriations, and China
  • Extensive relationships with Members of Congress and key leadership and committee staff
  • Only House Republican aide in modern history to serve on the floor teams of the Majority Whip, Majority Leader, Minority Leader, and Speaker

John Leganski is a former senior advisor to House Republican Leadership with over a decade of experience on Capitol Hill, most recently serving as Deputy Chief of Staff to Speaker Kevin McCarthy (R-CA). He brings clients a deep understanding of every aspect of the policymaking process, from effective coalition building and communications strategies to floor procedure and the ever-changing politics of the U.S. House of Representatives.

Best known for his role as McCarthy’s top floor lieutenant during the historic contest for Speaker, John was at the center of every major policy debate in the House during the Trump and Biden administrations, holding a number of senior positions in each of McCarthy’s elected leadership offices. He was credited by CNN’s Phil Mattingly with devising the internal strategy that jumpstarted House passage of the landmark Tax Cuts and Jobs Act of 2017, and personally served on the negotiating team that produced the Fiscal Responsibility Act of 2023 with the White House to raise the debt limit.

In advance of the 2022 midterms, John was the staff lead for drafting the Commitment to America, an ambitious policy platform assembled in coordination with all Republican leadership and committee front offices that House Republicans would campaign on and subsequently govern from in the 118th Congress. He was also instrumental in developing the House rules framework that created the Select Committee on China. In Congresses prior, John advanced the Innovation Initiative, a bipartisan agenda co-chaired by then-Majority Leader McCarthy and Representative Patrick McHenry (R-NC) that connected Silicon Valley stakeholders with Washington lawmakers on issues surrounding technology, data, and entrepreneurship.

Recognized by national publications including Politico, Roll Call, The Hill, Punchbowl News, and The Washington Examiner for his efforts in the House, John has shepherded hundreds of bills to passage spanning every committee, from tax extenders and trade agreements to annual government funding legislation and must-pass authorization bills. To date, he is the only House Republican staffer in modern history to have served on the floor teams of the Majority Whip, Majority Leader, Minority Leader, and Speaker.

John is a native of Chicago, Illinois, and a graduate of Stanford University.

Kyle Nevins


“Understanding what makes members tick isn’t an exact science, but Kyle Nevins spent more than a decade on Capitol Hill honing his skills to do just that as a senior staffer in Republican House leadership.”
  • Former top aide to the Congressional Leadership
  • Deep expertise in the legislative process, with a focus on the U.S. House of Representatives
  • Extensive Executive Branch engagement experience
  • Author of Inside Congress: A Guide for Navigating the Politics of the House and Senate Floors
  • Guest lecturer at The Brookings Institute
  • Board Member of the Frank Batten School of Leadership and Public Policy and the Center for Effective Lawmaking

Kyle Nevins is a seasoned former top aide to the House Republican Leadership with extensive experience in the process and politics of the U.S. Congress.  He specializes in a wide variety of business community and advocacy issues and has been recognized for his government affairs work by Politico Magazine as one of “50 Politicos to Watch” and The Hill as one of Washington’s “Top Lobbyists.”  Prior to co-founding Harbinger Strategies, Kyle spent two years as Principal at Capitol Counsel.

Kyle’s congressional career spanned over a decade in the U.S. House, serving as Deputy Chief of Staff to then-Majority Leader Eric Cantor (R-VA), as well as Director of Floor Operations to then-Republican Whip Roy Blunt (R-MO).  Kyle helped lead the House Republican vote-counting operation throughout the 2000s, influencing key policy decisions during both the Bush and Obama Administrations.  Following Republicans retaking of the majority in 2011, Kyle oversaw House committee and floor activity, guiding the chamber’s legislative strategy on impactful policy accomplishments, including trade agreements, the JOBS Act, and the so-called “fiscal cliff.”  His work on Capitol Hill was recognized in National Journal, Politico, Roll Call, and The Hill.

In 2011, Kyle helped establish the modern House of Representatives’ calendar and legislative schedule, instituting reforms that both parties have adhered to since.  Kyle testified before the House Select Committee on the Modernization of Congress in 2019, providing the committee with insight into the legislative scheduling process.

Kyle sits on the Advisory Board of the Frank Batten School of Leadership and Public Policy at the University of Virginia, as well as the Center for Effective Lawmaking (CEL), a joint research initiative of the University of Virginia and Vanderbilt University.  He lectures on the House’s policymaking and vote-counting process for The Brookings Institute and has written on congressional institutional reforms in The Federalist Society.

Kyle is a 2002 graduate of Duke University and studied at University College London.

Manny Rossman


“Manny built a highly effective whip organization. At the same time, he developed countless relationships with other Senate leadership offices, with House leadership offices, and with the administration that to this day facilitate the smooth operation of the entire legislative process.”
  • Former top aide to Senate Republican Leadership specializing in tax policy, legislative strategy, and Senate procedure
  • Deep expertise in legislative and regulatory policy matters, including financial services, health care, transportation, and international trade
  • Designs and implements winning strategies for a diverse group of Fortune 100 companies and major business trade associations
  • Extensive experience in analyzing and articulating legislative and regulatory risk and opportunities
  • Recognized by a variety of major publications for legislative expertise

Manny Rossman is a Capitol Hill veteran with two decades of experience in the U.S. Senate and House of Representatives, and in representing a diverse group of companies and trade association interests before Congress and the Administration.  Prior to co-founding Harbinger Strategies, Manny was Principal in the Breaux-Lott Leadership Group, a subsidiary of Squire Patton Boggs LLP.

During his congressional staff career, Manny served as Chief of Staff in the Office of the Senate Republican Whip, first for Senator Trent Lott (R-MS), and then for Senator Jon Kyl (R-AZ).  As Chief of Staff, he was the lead advisor to the Whip and responsible for formulating strategy, building support, and implementing the legislative priorities of a diverse caucus.  Manny directed a staff engaged in vote counting, policy formation, external communications, and Senate floor activities.  Manny also led outreach from the Whip office to all Senate and House Leadership offices, committees and Member offices, and to the Bush and Obama Administrations.

Before his Chief of Staff appointment, Manny focused on the legislative activities of the Senate Finance Committee for Senator Lott, playing a leading role in shaping major tax, international trade, health care, energy, and pension legislation before the committee and the Senate, including the Gulf Opportunity Zone Act, the Dominican Republic-Central America Free Trade Agreement, and the Tax Increase Prevention and Reconciliation Act.

Prior to that, Manny served as Legislative Director to Congressman Phil Crane (R-IL), then-Chairman of the House Ways & Means Trade Subcommittee, during which time he contributed to numerous tax and international trade bills, including the American Jobs Creation Act as well as free trade agreements with Chile, Singapore and Australia.  Manny began his career on Capitol Hill while in college, working for Congressman Bill Archer (R-TX), then-Chairman of the House Ways & Means Committee.

Manny’s policy expertise, knowledge of Senate floor procedure, and legislative acumen have been recognized in publications including the National Journal, the Washington Post, The Hill, Politico and Roll Call newspaper, which named him a “Fabulous 50” staffer on Capitol Hill citing his legislative expertise, ability to drive results, and access to key lawmakers.  He is a graduate of Colgate University as well as the University of Pennsylvania School of Law.

Jonathan Slemrod


“Jonny is one of the best policy minds in Washington and was a key member of my staff. His experience in multiple Senate offices and the Office of Management and Budget gives him a unique ability to translate policy to results.”
  • Former advisor to Senate Republican Leadership, Senator John Cornyn (R-TX), and Senator Marco Rubio (R-FL)
  • Served as a top aide to the White House Office of Management and Budget (OMB) and Consumer Financial Protection Bureau (CFPB)
  • Deep expertise in budget and appropriations, financial services, tax, trade, and health care policy, as well as Congressional committee and floor procedure/process
  • Expert in coalition building, management, and advocacy efforts

Jonathan Slemrod is a seasoned operative who helps clients navigate complex policy issues including budget/appropriations, energy, financial services, labor, tax, trade, and oversight matters in front of Congressional committees. He served as a top advisor at the Office of Management and Budget (OMB), for Senate Republican Leadership, House and Senate Republicans, and on a competitive presidential campaign. He has been named as a “Top Lobbyist” by The Hill newspaper from 2019-2023. In addition to direct lobbying, Jonathan has a track record of successful coalition building/management and campaign-oriented advocacy efforts, helping companies, campaigns, non-profits and trade associations achieve policy victories through unconventional and effective means.

From 2017-2018, Jonathan served as Associate Director for Legislative Affairs at the Office of Management and Budget (OMB). In this role, he was OMB’s lead liaison to Congress during bipartisan negotiations on government funding and authorizing issues. He worked closely with Republican and Democratic Leadership, committees, members of Congress, numerous White House offices and agencies to craft and communicate OMB’s official position on legislation and regulation.

Concurrent with his role at OMB, Jonathan was Special Advisor to the Acting Director of the Consumer Financial Protection Bureau (CFPB), helping the Bureau’s leadership navigate its committees of jurisdiction. Jonathan also managed the successful Senate confirmation of the permanent Director of the CFPB.

From 2013-2017, Jonathan served on the leadership staff of Majority Whip Senator John Cornyn (R-TX), advising Senator Cornyn and the Whip team on budget, tax, and trade policy. Slemrod managed outreach with conservative and business/employer organizations, organizing multiple successful coalitions. In 2012, Jonathan worked on the leadership staff of Minority Whip Senator Jon Kyl (R-AZ) handling tax policy.

Outside of Congress, Jonathan worked as Policy Director for the Marco Rubio for President campaign, acting as the candidate’s top policy advisor and managing an extensive network of policy surrogates. Earlier in his career, Jonathan was Legislative Assistant to Senator Rubio, handling economic issues. He also worked for Congressman Paul Ryan (R-WI).

Jonathan is a native of Ann Arbor, Michigan, and a graduate of the University of Michigan.

Steve Stombres


“Mr. Stombres has been part of the Republican brain trust for most of the legislative fights in recent years, serving at Mr. Cantor’s side as the lawmaker rose to be second in command behind Speaker John A. Boehner. Mr. Stombres is part of a small group of Republican aides who plot out the party’s tactics on taxes, spending, foreign affairs, social issues and jobs.”
  • Second highest ranking staffer in the U.S. House of Representatives with 21 years of congressional experience
  • Former Chief of Staff to House Majority Leader, Republican Whip, and Chief Deputy Whip Eric Cantor
  • In-depth policy expertise in defense, foreign affairs, financial services, tax, and trade
  • Mayor of Fairfax from 2016-2017 and Fairfax City Councilman from 2008-2014
  • Retired 20 year Intelligence Officer in the U.S. Army Reserve

Steve Stombres is a knowledgeable and effective advocate for Harbinger’s clients who benefit from his diverse career of service on Capitol Hill, as an elected official, and as an officer in the U.S. Army.

During his time as a Leadership Chief of Staff, Steve was a trusted negotiator for House Republicans on several high-profile legislative battles.  He was personally involved in resolution of the debt limit crisis of 2011, the fiscal cliff of 2012, and the government shutdown of 2013.  Steve’s role in the 2011 debt limit discussions were described in detail in Bob Woodward’s best-selling book, The Price of Politics.  Steve appeared on Roll Call’s “Fabulous 50” list of the most influential staffers on the Hill for over ten years and was described by The New York Times as “one of the most powerful Republican aides on Capitol Hill.”

In addition to his time as Chief of Staff to the offices of the Chief Deputy Whip, the Republican Whip, and the Majority Leader, Steve served as personal office Chief of Staff to Rep. Eric Cantor, as well as various policy positions throughout the House and its committees.

Outside of Congress, Steve was elected to the Fairfax City Council in 2008, serving three consecutive terms before retiring in 2014.  In 2016, Steve was sworn in as the 11th Mayor of the City of Fairfax and served until February of 2017.

Steve’s government service also includes a distinguished military intelligence career.  Steve first enlisted in the U.S. Army Reserve in 1987 and was a 1995 graduate of Officer Candidate School (OCS).  Upon receiving his commission, he served as an intelligence officer and was assigned to the Defense Intelligence Agency.  In 2003, Mr. Stombres was mobilized in support of Operation Iraqi Freedom and served on the Joint Chiefs of Staff as an Iraq Analyst for the Iraq Intelligence Task Force.  He retired from the Army Reserve in 2009.

Steve graduated from the Virginia Polytechnic Institute in 1993 and holds a B.A. in History.

A team of professionals, dedicated to providing world-class results.

Each partner of the Harbinger Strategies team has been involved at the highest levels of decision-making in Congress, the Executive Branch, and national political campaigns.  Relying on our deep experience, we deliver results for our clients in any political environment.

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