Republicans sought to cover their conservative flank by pointing Wednesday at the slate of high-profile conservatives who've backed the GOP's tax deal with President Obama.

Republican staff on Capitol Hill circulated the growing list of high-profile endorsements for the tax deal amid rumblings that some conservatives could end up opposing the tax plan.

The GOP pointed to statements of support from former House Speaker Newt Gingrich (R-Ga.), the U.S. Chamber of Commerce and Grover Norquist of the conservative Americans for Tax Reform, along with laudatory statements from some conservative writers and think-tankers to promote their tax deal. 

Another major endorsement came from FreedomWorks, a major Tea Party umbrella organization, which said it could accept the deal.

"I am writing today to offer our support for the general framework for the compromise tax proposal announced by President Obama and leaders in Congress," FreedomWorks President and CEO Matt Kibbe wrote to senators. "It is not our ideal proposal, but it is worth supporting while concurrently pushing for a major overhaul of the entire tax code and major spending reductions."

The push comes as some high-profile conservatives, including Sen. Jim DeMint (R-S.C.), say they would vote against the plan, complaining about the 13-month extension of unemployment benefits included as part of a compromise with the White House to extend all tax rates for two years.

But even groups like the Club for Growth, the fiscally conservative organization that's been politically active in GOP primaries, have said they wouldn't necessarily plan primaries for Republican lawmakers who back the final deal — despite the Club's opposition to the plan.

GOP staff also pointed to a Gallup poll showing many self-identified Republicans (85 percent) would support extending the tax cuts for two years, and that 43 percent of Republicans would support the unemployment extension.

Updated Dec. 9 at 7:48 p.m.