Most Senate Republican leaders are hoping earmarks make a comeback, but after bowing to pressure from House Republicans and conservative elements in their Conference in 2010, some concede it might be difficult to roll back a self-imposed limit that remains politically popular with the GOP base.

The current temporary moratorium adopted by Senate Republicans and Democrats is set to expire at the end of this Congress, but with Republicans looking to control the House and Senate after the November elections, a return to Congressionally directed spending appears unlikely anytime soon.

“I am a … recovering earmarker, like many of us are around here,” Senate GOP Conference Chairman John Thune (S.D.) said.

“But I do think that the process has been abused. If we are ever going to return to an era where Congress has more of a role when it comes to appropriations, I think it’s going to be with significant changes and reforms. But at this point, everybody is sort of in agreement that the best thing to do is to keep the ban on.”

Sen. Roy Blunt (Mo.), Republican Conference vice chairman, said he could see a possibility for the return of earmarks. Blunt is a member of the Appropriations Committee, which, until the moratorium, had been the typical venue for earmarking.

Senate Minority Whip Jon Kyl (R-Ariz.) also said he believes that earmarks could return but only under a clear definition.

“There are still some questions about exactly what an earmark is,” said Kyl, who is retiring at the end of the year. “We have to have a common definition that everyone agrees to … and it’s fine with me to have that done in statute.”

But Senate Republican Policy Committee Chairman John Barrasso (Wyo.) thinks earmarks could be gone for good: “I think the American people are right that earmarks have been a significant problem. That is why I support the moratorium.”

Asked whether he thinks they will return, Barrasso said, “Hopefully no time soon.”

Minority Leader Mitch McConnell (R-Ky.) is key to how the Senate Republicans handle the issue.

As a longtime member of the Senate Appropriations Committee, McConnell is no stranger to earmarks and is known for his savvy political instincts.

That is why there was a collective gasp when McConnell — who had been an eloquent defender of the practice as one of Congress’ core responsibilities in controlling the power of the purse — agreed to the moratorium in November 2010.

McConnell’s move was more political necessity than a change of heart, sources said.

One Republican lawmaker said the Kentucky lawmaker was pushed to the right on the issue by the new makeup of the Conference after the 2010 elections, which saw a wave from tea-party-inspired candidates.

“He can count,” the lawmaker said. “That is the Mitch McConnell I know.”

McConnell’s spokesman pointed to his vote, and that of other GOP leaders, in favor of a permanent earmark ban amendment and to his speech in November 2010 in which he declared he had heard voters’ discontent and pledged to lead by example on “changing the way we do business, even on things we have defended in the past, perhaps for good reason.”

But since that speech, McConnell has not publicly weighed in on the debate other than voting for earmark-limiting amendments offered by other Senators.

The Senate GOP adopted a temporary ban for the current Congress after House Republican leaders made the move. But questions remain if the moratorium will be made permanent, given that champions continue to press for votes in the Senate.

Sens. Pat Toomey (R-Pa.) and Claire McCaskill (D-Mo.) have pledged to take every opportunity to force a vote on a proposal to make the current two-year moratorium permanent. A possible vote could come this week in connection with the surface transportation bill on the Senate floor.

The Senate voted earlier this month, 40-59, against making the ban permanent, with most GOP leaders (except for Blunt) supporting the proposal. Overall, seven Democrats voted for the ban and 13 Republicans voted against it.

Even without an amendment, what Senate GOP leaders decide could be dictated by the House GOP position and the posture of the next president. President Barack Obama opposes Congressional earmarks.

Speaker John Boehner (R-Ohio) “is not going to allow earmarks, so the question is moot,” one senior Republican aide said.

Senate Democrats are also not all on the same page regarding earmarks, but their top leaders all support going back to allowing Member-directed spending.

Earmarks have also suffered from recent scandals, which made the term “a dirty word,” said Steve Ellis, vice president of budget watchdog group Taxpayers for Common Sense. Lobbyists and lawmakers have gone to jail in recent years for linking campaign contributions to earmarks.

But there are still some GOP old bulls who believe earmarks should come back.

“I supported the moratorium to clean up the earmark process and to help as a part of the leadership gain consensus within our caucus, so I supported that,” said Sen. Lamar Alexander (Tenn.), who served as Republican Conference chairman before stepping down from leadership at the beginning of this year.

“But I’m still not ready permanently, to tell some Tennessean who comes and says to me: ‘What are you going to do about the Center Hill Dam, which is unsafe and which, if it fails during a flood, will put four feet of water into the city of Nashville?’ I’m not comfortable saying to them, ‘Well, all I can do about it is give you President Obama’s telephone number,’” he said.

But, sensing their momentum, earmark foes hope that the more they bring the issue up, the more political pressure will come to bear.

“I think [that] to vote against a moratorium on earmarking would be a very dangerous vote,” McCaskill said at a press conference last week.