jim_demint.jpgWASHINGTON (AP) _ Sen. Jim DeMint, patron saint of the tea party and a would-be Republican kingmaker, announced suddenly Thursday he would resign his South Carolina seat to head Washington's conservative Heritage Foundation think tank, a shift that reverberated through a soul-searching GOP.

Just two years into a second, six-year term, DeMint said he would step down on Jan. 1 to helm Heritage while continuing the conservative fight. The 61-year-old lawmaker, known to hurry home to South Carolina nearly every weekend, had signaled that this term would be his last, but his abrupt announcement shocked even his closest Republican colleagues.

“When he told me this morning, I about fell off my couch,'' said South Carolina's other senator, Republican Lindsey Graham. “I didn't see this coming.''

Prizing ideology over electability, DeMint sometimes infuriated fellow Republicans, picking sides in GOP primaries with decidedly mixed results. He had no patience for centrist Republicans, pushing the party to the right while bankrolling candidates with millions from his political action committee, the Senate Conservatives Fund.

In 2010, candidates he ardently supported cost the GOP eminently winnable seats. This year, DeMint had better success.

“One of the most rewarding things I've done in the Senate is work with the grassroots to help elect a new generation of leaders who have the courage to fight for the principles of freedom that make this country so great,'' DeMint said in his statement announcing his departure. “I'm confident these senators will continue the legacy of conservative leaders before them.''

DeMint also has sometimes been a thorn in the GOP side on legislation, just this week criticizing House Speaker John Boehner's “fiscal cliff' counteroffer to President Barack Obama that would raise tax revenue $800 billion as crushing for American jobs.

DeMint's departure creates an opening for a new generation of hard-charging conservatives in the Senate _ Rand Paul of Kentucky, Mike Lee of Utah and soon-to-be Sen. Ted Cruz of Texas. The strong conservative element is pitted against the establishment as the Republican Party tries to figure out its next moves after this year's defeat in the presidential race and the loss of congressional seats.

Shocked Senate Republicans were too courteous to say good riddance to DeMint, but a few made it clear that there were still hard feelings over the senator's political moves.

“I won,'' Sen. Lisa Murkowski, R-Alaska, said tersely when asked about DeMint backing her Republican primary rival Joe Miller in 2010, forcing her to run as a write-in candidate.

Democrats pointed out that they increased their numbers in this year's elections and will hold a 55-45 edge in the Senate next year.

“His effect on the system may have been more beneficial to Democrats than to Republicans,'' said Sen. Chuck Schumer, D-N.Y.

Sen. John Cornyn, R-Texas, who headed the National Republican Senatorial Committee in 2010 and this year, said he and DeMint agreed as conservatives “on 95 percent of the issues, it's a lot of it has to do with tactics to advance the conservative cause through the electoral process. I wish him well.''

Delaware and Colorado in 2010 are sore points for Republicans who were certain they could win the Democratic-held seats. DeMint backed Christine O'Donnell who prevailed over the more electable Rep. Mike Castle in the GOP primary; Democrat Chris Coons easily beat O'Donnell that November.

In Colorado, DeMint supported conservative Ken Buck who stumbled in his race against Democratic Sen. Michael Bennet.

Yet for the defeats, there are several Republicans who owe their seats to DeMint, and they expressed appreciation for a man they consider the chief instigator of the tea party movement.

“We have a much bigger liberty caucus in the Senate than we did before,'' Paul said. “I think a lot of that is thanks to Jim DeMint.''

Said Florida's Marco Rubio: “I would not be in the U.S. Senate had it not been for Jim DeMint taking a shot on me.''

In an interview with conservative radio host Rush Limbaugh, DeMint said he was frustrated with the Republican Party when it held the majority during the George W. Bush administration.

“It's part frustration, but I am also reassured that we have now stocked the Senate with some of the strongest conservatives in the country today and that's a big change. So I'm leaving the Senate better than I found it,'' DeMint said.

Senate Republican leader Mitch McConnell of Kentucky said DeMint forced Washington to address economic issues.

“There is no question in my mind that he raised the profile of important issues like spending and debt and helped galvanize the American people against a big government agenda,'' McConnell said in a statement.

DeMint's exit ensures a far more lucrative future for him than the annual Senate salary of $174,000. Edwin Feulner, the man DeMint will replace, made more than $1.2 million last year.

DeMint's decision creates an opening in South Carolina and the prospect of two elections in November 2014.

Republican Gov. Nikki Haley will pick a successor to serve two years until the next election. Among the potential candidates are several House members, including Rep. Tim Scott, who would be the first African-American Republican senator in decades.

The opening also ensures that much of the state's attention will be focused on that race while Graham seeks another term. A primary challenge to Graham now seems unlikely although he and DeMint have clashed at times.

“You could say what you like about the tea party, but without the tea party none of us would be talking about fiscal issues like we are today,'' Graham said. “Jim's biggest legacy is creating energy for those who believe in limited government.''

Graham called DeMint “a strong voice. He didn't mind disagreeing with his colleagues. At the end of day I think the movement that Jim helped start is going to be alive and well in 2014.''

DeMint had recently stepped aside as head of the Republican Steering Committee, handing off the chairmanship to first-term Sen. Pat Toomey, a conservative he backed for the Pennsylvania seat held by Sen. Arlen Specter.

DeMint was poised to become the top Republican on the Senate Commerce, Science and Transportation Committee with the retirements of Sens. Kay Bailey Hutchison of Texas and Olympia Snowe of Maine. The position would have given him a major say over highways, the Coast Guard and navigation issues.

Republican Sen. Richard Shelby of Alabama, who has been in the Senate since 1987, said DeMint's decision reflects the markedly different outlooks of various lawmakers.

“People have different mind-sets, different goals,'' Shelby said. “Some people come up for a term or two terms, or a term and a half and leave and go on to different things. Some people come up to be long-distance runners, to make a difference, to work within the institution.''

Joked Sen. Roy Blunt, R-Mo.: “I think it's actually a good fit and it moves me up in the Commerce Committee.''