Sen. Jim DeMint’s abrupt resignation Thursday from his Senate seat to run the conservative Heritage Foundation will leave the chamber without its leading tea party voice and potentially reverberate in GOP Senate primaries across the country.

The South Carolina Republican announced that he’d replace Ed Feulner as president of The Heritage Foundation in January.

“This is a critical time for America and there is no organization in the country, in fact, the world, that is better positioned to convince the American people that the conservative policies that The Heritage Foundation has developed over the years are the solutions to the problems that we face as a nation,” DeMint told a handful of reporters after he was introduced to staffers at the foundation’s headquarters just blocks from the Senate.

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“This family of conservatives here at The Heritage Foundation helped to shape my own views,” he added. “They inspired me to run for Congress in the first place, and they’re in a position now to carry the message that we need to carry to the American people.”

Senate Minority Leader Mitch McConnell said DeMint called him Thursday morning to tell him he was stepping down.

“We’re sorry to see Jim go. He’s had a distinguished career,” McConnell told POLITICO in a brief interview. “My wife [Elaine Chao] is a distinguished fellow at The Heritage Foundation. She’ll be reporting to him.”

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In an earlier written statement, DeMint said it had been an honor to serve the people of South Carolina for the past eight years but “now it’s time for me to pass the torch to someone else and take on a new role in the fight for America’s future.

“I’m leaving the Senate now, but I’m not leaving the fight,” he said.

DeMint also appears poised for a raise, with Feulner pulling in $1.03 million in 2010, according to public records. DeMint earned $174,000 in 2012 as a senator.

At Heritage headquarters north of the Capitol, dozens of staffers filed into a first-floor auditorium to hear the announcement directly from DeMint, whose muffled voice could be heard emanating from the room. Several speeches were punctuated by laughter and applause.

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The mistake the GOP made over the past four years, DeMint told reporters, was focusing too much on what the party was against rather than putting forth “bold ideas to get people inspired and behind us.”

“Heritage has those ideas,” he said, sporting a blue Heritage tie with liberty bells. “I honestly believe I can do a lot more on the outside than I can on the inside.”