Senate Republicans called Democrats’ bluff on Thursday night and refused to bow to pressure to pass a $410 billion omnibus spending bill by Friday.

Though both Speaker Nancy Pelosi (D-Calif.) and Senate Majority Leader Harry Reid (D-Nev.) had said they would simply pass the omnibus with no new funding priorities if the Senate didn’t meet their Friday deadline, both leaders agreed to Senate GOP demands for more time to debate it on the Senate floor.

After allowing votes on 12 Republican proposals this week, Reid agreed to vote on 13 more GOP-sponsored amendments before a vote on final passage that is expected Tuesday afternoon. The bill must first overcome a Republican-led filibuster attempt on Tuesday, which requires 60 votes for passage.

The amendment list — agreed to on Friday morning — includes votes to extend a District of Columbia school voucher program, as well as proposals on labor laws and the so-called “fairness doctrine— for broadcasters.

Several Republicans — who nonetheless are prepared to vote in favor of the bill —told Reid on Thursday night that they would withhold their votes until more of their colleagues were able to offer amendments. Because two Democrats — Sens. Russ Feingold (Wis.) and Evan Bayh (Ind.) — were expected to oppose the measure, Reid needs four GOP Senators to vote with Democrats. Only three — Sens. Thad Cochran (Miss.), Richard Shelby (Ala.) and Kit Bond (Mo.) — appeared ready to do that Thursday night.

“We thought we were going to finish it last night,— Reid said on the floor Friday morning. “A significant number of Republicans wanted some more amendments. As a result of that, a number of my Republican friends called me and said, We think that we need more amendments. We know that we said we were going to vote to end the debate, but we feel there’s more debate.’ I wish I hadn’t received those calls, but I understand … how the Senate works.

“No one broke their word to me. It was just a misunderstanding. We’re where we are.—

Indeed, Maine Republican Sen. Susan Collins was among those Thursday who wanted additional debate before she would consider voting for the bill.

“I think there should be more amendments,— she said.

The decision to allow more debate time forced Pelosi and Reid to bring up another stopgap spending bill, or continuing resolution, that will keep the government funded through Wednesday, but provide no new authority for federal projects. A similar temporary spending bill that has kept the government funded at last year’s levels since last fall expires Friday at midnight.

Both chambers are expected to approve the CR on Friday afternoon.

Still, Democratic leaders do not appear to be budging on their insistence that the Senate reject all amendments to the House-passed omnibus, and are continuing their threats to pass a long-term continuing resolution if any changes are adopted to it in the Senate.

“We will work to defeat every one of them,— said one senior Senate Democratic aide.

Jessica Brady contributed to this report.