Updated: 11:10 a.m.

Sen. Jim Bunning (R-Ky.) on Friday morning continued his one-man crusade to block a one-month extension of unemployment and health insurance benefits until Democrats agree to use stimulus funding to pay for them.

Because existing funding for unemployment and COBRA health insurance expire Sunday, Bunning’s filibuster means the federal government will be forced to stop sending payments to the jobless beginning Monday, Democratic and Republican aides said.

Senate Majority Whip Dick Durbin (Ill.) led a contingent of Democratic Senators to the chamber floor just after 7 p.m. Thursday, and for the next four and a half hours engaged in an often heated debate with Bunning over his objections to the benefits’ extension.

The floor fight was a rare one for a typically stoic Senate. Durbin, hoping to wear down the 78-year-old Bunning, asked for an agreement on the benefits’ extension every half-hour, and in the meantime, he and his colleagues — including Sens. Claire McCaskill (D-Mo.), Jeff Merkley (D-Ore.) and Bernie Sanders (I-Vt.) — castigated Bunning.

Bunning, who is retiring at the end of this Congress, was unswayed and could be heard yelling obscenities at his Democratic colleagues during a colloquy between Durbin and Merkley.

Bunning continued his objections into Friday morning, and during a brief exchange on the Senate floor it was clear that neither he nor Durbin had softened his position.

“When you look at this hardship that many Americans are facing, through no fault of their own, and despite their heroic efforts to put their lives back on track, I believe it is unthinkable, unforgivable that we would cut off unemployment insurance payments to these people, that we would cut off COBRA payments. … And yet, that’s what’s going to happen Sunday night. It’s because the Senator from Kentucky has objected,” Durbin argued, adding that it is wrong for the Senate to “go home to our home states, to the loving arms of our famil[ies], to a relaxing weekend and know that Sunday night unemployment checks would be cut off across America.”

But Bunning remained defiant, arguing that the Senate must learn to pay for its spending and curb its deficit spending. “We cannot allow that to happen, because I have got too many young grandchildren that want America to be the same America that I grew up in. And I’m worried to death that that’s not going to be the case,” Bunning said.

GOP aides stressed Thursday night that Bunning did not have the backing of his leadership for his filibuster. Indeed, according to aides on both sides of the aisle, Bunning on Wednesday torpedoed a deal cut by Minority Leader Mitch McConnell (R-Ky.) and Majority Leader Harry Reid (D-Nev.) to allow a vote on the funding proposal.

In a floor speech Wednesday, Bunning seemed to acknowledge that he had rejected the deal. “Of course, we can have a vote on it, and, of course, it can be defeated, and then, of course, we can pass the bill without the money. I am not willing to risk that $10 billion being added to the deficit. I was not ready to risk voting on a bill I knew would not get the amount of votes necessary to pay for it. If the Majority Leader would have included it in his [unanimous consent agreement], I would have had no problems. But he did not include it in his UC. So that was the reason I asked to pay for it,” Bunning said on the Senate floor Wednesday.

With no support from leadership, Bunning was forced to man the GOP side of the chamber on his own. Toward the end of the evening, a clearly frustrated Sen. Bob Corker (R-Tenn.) came to the Senate floor to mount a quasi-defense of his Kentucky colleague. Corker didn’t defend Bunning’s position outright, but he did argue that Democrats had sandbagged Bunning — and in so doing treated him unfairly — with their hours-long attempt to break his filibuster.

“If the attempt tonight is going to be to keep a man 20 years my senior here without the knowledge that this was going to happen … this, in my opinion, is beneath the Senate. And while I might be weary, I will stay here the entire night to defend the Senate and defend the fact that the Senator from Kentucky did not know this was going to happen,” Corker said.

It remains unclear whether the Senate will be able to work out a deal on the extensions anytime soon. On Monday, the Senate is expected to begin work on a yearlong extension of those programs as part of a broader jobs bill, but Democrats said they will continue to try and find a fix in the meantime.

“We will be back. We will try to get this done. And to those families, hang in there. After the politicians are finished with their speeches and debates, America’s not going to give up on you. It’s going to be tough for a while while we work out this political difference, but unfortunately that reflects the Senate where it is today,” Durbin said.

Jessica Brady contributed to this report.