After graduating from law school, he clerked for Associate Justice Peter T. Zarella of the Connecticut Supreme Court and was appointed by Connecticut GovernorJodi Rell to serve on the Judicial Review Council from 2009 to 2013. Clark was a co-founder of the Connecticut-based law firm Davis, Clark & Bonafonte LLC, where his practice focused on litigation in state and federal trial and appellate courts. He also provided general counsel services to clients, advised them on compliance matters, and represented them before various regulatory bodies. As a part of that practice he served various state and national campaigns and committees. He served as General Counsel to the Connecticut Republican Party and managed the Tom Foleygubernatorial campaigns in 2010 and 2014. He was also political director for Linda McMahon's 2012 United States Senate campaign. In 2015, he served as General Counsel to Matt Bevin's gubernatorial campaign in Kentucky where, among other things, he successfully developed and executed the plan to preserve an 83-vote margin in a recanvass of votes in the May primary. Prior to joining the Donald Trump 2016 presidential campaign, Clark served as Director of Operations for Chris Christie 2016 presidential campaign where he helped develop and manage the budget, develop and implement a fifty-state ballot access program, and managed the travel and advance staff. Clark was hired by Donald Trump's presidential campaign in March 2016 as the campaign's Connecticut state director, and later served as an advisor to the campaign during the Indiana Republican primary in May 2016. In June 2016, he was named Deputy National Political Director of the campaign and served in that capacity through the end of the election. In that role he developed and implemented a 50-state political and field strategy and during the 2016 Republican National Convention, served as one of the chief whips for the campaign on the rules committee and on the floor. He later headed the campaign's recount efforts in Michigan and served as the chief whip for the campaign in the electoral college. After the election, Clark served on the Presidential transition team. Clark became the President's Director of Intergovernmental Affairs on January 20, 2017. He was appointed the Director of Public Liaison in March 2018. In that role, Clark oversaw the political aspects of the nomination of Brett Kavanaugh to the U.S. Supreme Court. In December 2018, Clark and White House political director Bill Stepien were named Senior Political Advisors to the President's re-election campaign focusing on delegate and party organization. Clark is also Senior Counsel to the President's re-election campaign focused on compliance and election day operations. In 2019, Clark was surreptitiously recorded telling Wisconsin Republicans that "traditionally it’s always been Republicans suppressing votes in places" and that 2020 would be the time to "start playing offense a little bit" to protect their voters. In response to the recording, Clark said "Republicans historically have been falsely accused of voter suppression." In 2020, Clark was appointed as a member of the President's Commission on White House Fellowships.
