But not all Republicans agree. DeMint often was at loggerheads with the party’s election apparatus, which more often than not was looking for House and Senate candidates with the best chances of winning and leading the party to a congressional majority, instead of which candidates were more conservatively pure.

“The priority is not first the majority,” DeMint told McClatchy in 2010. “We had a big majority with 55 Republican senators. We had a big House majority. We had Bush in the White House. We spent too much, borrowed too much – and they (the voters) threw us out.”

Even on his way out of office, DeMint thumbed his nose at House Speaker John Boehner this week for his counterproposal to Obama to avert the fiscal cliff.

“Speaker Boehner’s $800 billion tax hike will destroy American jobs and allow politicians in Washington to spend even more, while not reducing our $16 trillion debt by a single penny,” he said. “This isn’t rocket science.”

DeMint and Sen. John Cornyn, R-Texas, the chairman of the National Republican Senatorial Committee, argued over campaign tactics. Cornyn complained that DeMint, by inserting himself and his money into some races, contributed to defeats.

DeMint-backed candidates such as Rubio and Sens. Rand Paul of Kentucky, Mike Lee of Utah, Patrick Toomey of Pennsylvania and Ron Johnson of Wisconsin all are sitting at desks in the Senate chamber.

But some Republicans complain that DeMint cost the party winnable seats by throwing his support or resources to candidates such as Richard Mourdock, who failed to win the seat last month held by outgoing Sen. Richard Lugar, R-Ind., and Delaware’s Christine O’Donnell, who defeated moderate Republican Rep. Mike Castle in the 2010 primary for a Senate seat but was crushed by Democrat Chris Coons in the general election.

Sen. Tom Coburn, R-Okla., a fellow conservative who followed DeMint from the more free-wheeling House to the more buttoned-down Senate, noted that it hasn’t always been easy for DeMint to be the crusader of conservative causes.

“He was an anchor for conservative principles and he was willing to take all the heat in the world because of what he believed in, and he learned how to do it effectively,” Coburn said. “We both had a learning curve here. We didn’t do it effectively at first. We’ll miss him. It’s going to be a big void.”

DeMint still has a few more weeks to roam the Senate chamber and halls in this lame duck session before he joins his few dozen fellow zombies.