Senate Republicans complained Thursday that a high-profile vote on a temporary earmark ban would be pushed back until late in the night, limiting press coverage and possibly preventing presidential candidates from voting on the measure.

According to the office of Sen. Jim DeMint (R-S.C.), Republicans asked Senate Majority Leader Harry Reid (D-Nev.) to schedule the vote earlier in the day so that their presumptive nominee, Sen. John McCain (Ariz.), could cast a vote before returning to the campaign trail. But Reid declined, saying the vote wouldn’t occur until around midnight Thursday, if not later, according to DeMint aides.

The amendment has drawn strong opposition from both parties, including from Reid and senior members who say that Congress, not the executive branch, has the constitutional right to set funding priorities. But supporters of the DeMint amendment say that the earmarking practice is broken, leading to cases of congressional corruption, arguing that a temporary freeze in pet projects is needed to reform the practice.

The amendment, which would set a one-year moratorium on earmarks, is also supported by Democratic presidential candidates Sens. Barack Obama (Ill.) and Hillary Rodham Clinton (N.Y.), who are on Capitol Hill Thursday for an all-day voting session on the Fiscal Year 2009 budget.

Supporters appear to be short of the 60 votes needed for adoption, but the amendment has generated the most attention and has angered opponents who say they are not getting enough credit for the work they have done to make the process more transparent and limit the number of earmarks.

Jim Manley, a spokesman for Reid, said that DeMint would get a vote on the amendment, but did not say when it would occur.

“Sen. DeMint and every other Republican will get a vote on everything they want a vote on,” Manley said.