Gillespie won the nod at the Virginia Republican Convention in Roanoke to challenge Warner, a former Virginia governor and early favorite in the race. Gillespie is the former Republican National Committee chairman and a former adviser to President George W. Bush and Mitt Romney's 2012 presidential campaign. A onetime aide on Capitol Hill, Gillespie also has made millions as a corporate lobbyist.
Gillespie beat out three rivals for the nomination: insurance salesman and former Air Force pilot Shak Hill; congressional staffer Tony DeTora; and Chuck Moss, owner of at a network consulting business.
In a speech to thousands of GOP delegates prior to the convention vote in which he was the favorite, Gillespie promised to fight for lower taxes, fewer restrictions on energy production and to repeal the Affordable Care Act.
"I will take our fight to Mark Warner, I will lead us to victory in the fall and we can turn our great country around again," Gillespie said.
Republicans are waging a fight against supporters of Democratic President Barack Obama to gain the six U.S. Senate seats required to secure control of that chamber. Warner however, is an early favorite.
A race between Gillespie and Warner pits two multi-millionaires from northern Virginia who both worked as political operatives early in their careers.
Warner made his fortune as a cell phone pioneer. Gillespie worked as an aide to former U.S. House Majority Leader Dick Armey, and was part of the GOP's conservative "Contract with America" congressional movement in the 1990s. He later worked as a lobbyist and consultant for several Fortune 500 companies.
Hill tried to make the case that Gillespie's past as a lobbyist made him unelectable against Warner.
"I have the moral authority to challenge Mark Warner, not everyone in this race can make that claim," Hill had said.
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