Will they, or won’t they?

Senate Democrats and Republicans left a rare joint caucus meeting Monday evening without a deal to prevent Senate Majority Leader Harry Reid (D-Nev.) from going “nuclear” and changing the chamber’s rules. [WATCH VIDEO]

All eyes Tuesday morning were on the Senate floor, where some Democrats were optimistic Republicans would allow a vote to advance the nomination of Richard Cordray to lead the Consumer Financial Protection Bureau.

Such a move could buy more time for Reid and Senate Republican Leader Mitch McConnell (R-Ky.) to strike a deal to avert Reid from going nuclear. 

{mosads}A successful vote to advance Cordray would give Reid and McConnell eight hours of post-cloture debate to hash out a compromise on the nominees to the National Labor Relations Board.

Sen. John Thune (R-S.D.) told reporters Republicans might allow Cordray to proceed to a final vote, noting “the NLRB is the real point of contention.”

Reid offered few signals while speaking to reporters after Monday night’s long meeting.

“The night is late; we’ve [had] no breaks; we’ve been going steady,” Reid told reporters after the meeting, which spanned more than three hours. “We’ve had a very good conversation. The conversation is going to continue tonight. The votes are scheduled for 10 o’clock in the morning.”

Reid is expected to speak on the Senate floor Tuesday morning.

Senate Democratic Whip Dick Durbin (D-Ill.) described the conversation Monday night as positive in tone but ultimately, it failed to produce a resolution.

“There was a very good feeling. People got to express themselves without the media, and there was a very good feeling about some of the expressions, but at the end of the day, we didn’t come up with a solution,” he said. “The conversation’s going to continue.”

“A clear bipartisan majority in the meeting believed the leaders ought to find a solution. And discussions will continue,” said Don Stewart, a spokesman for McConnell.

Reid reiterated Monday morning that he could trigger the so-called nuclear option as early as Tuesday if Republicans do not agree to give up-or-down votes to seven of President Obama’s pending nominees.

By going nuclear, Reid would change the Senate’s rules to allow the nominees to be confirmed with a simple majority vote. The rule change would prevent the minority from filibustering nominations, which requires the majority to win 60 votes to get a nominee confirmed.

If Reid takes the controversial step, Republicans warn they will retaliate by enacting future rules changes that would allow the repeal of ObamaCare or other Democratic priorities with a majority Senate vote if they regain power.

Republicans were hopeful of a compromise before the joint session.

“We’ve shaped a compromise, but we don’t know if Sen. Reid will buy it,” Sen. John McCain (R-Ariz.) told reporters after meeting with the majority leader earlier in the day.

He conceded that a deal remained elusive after spending hours in the Old Senate Chamber debating the consequences of changing the rules with the nuclear option.

“It was a good hearing, a good meeting, good exchange of views, and still no conclusions,” he said. “We continue to negotiate, and we continue to talk, and then I’m afraid the majority leader may schedule a vote unless we reach some agreement.”

As the hours dragged into the late evening, senators shuttled to and from the restroom, shrugging aside questions from a crowd of reporters gathered in the Ohio Clock corridor outside the Senate chamber.

Earlier in the day, McCain warned a unilateral rules change could jeopardize further legislative action, citing a budget deal needed to raise the national debt limit at year’s end.

But Reid took a hard line early Monday when asked what the GOP could do to prevent him from using the nuclear option.

“Let them stop the filibuster on the seven that I filed cloture on, and we would have up-or-down votes on those people, and we go on to the business of the day,” he said during an appearance at the Center for American Progress Action Fund. “That seems pretty simple to me.”

Reid argued that the rules change would be relatively modest, as it would not affect the 60-vote threshold for advancing legislation or judicial nominations.

He said he is not exploring any other rules changes, with the caveat that “the Senate is an evolving body.”

Sen. Tom Harkin (D-Iowa) told reporters Monday evening that Reid has enough support from his caucus to force a rules change.

“We’ve got the 51 votes. We’ve got the 51 votes to change these rules. I can guarantee you,” he said.

Sen. Lamar Alexander (Tenn.), a former member of the Republican leadership who is close to McConnell, warned last week that Republicans could retaliate by ramming through a repeal of the Affordable Care Act, right-to-work legislation and other Republican priorities when they regain the majority.

Reid scoffed at the threat, predicting Republicans would not dare to eliminate filibusters of legislation if they were to recapture the upper chamber.

“If they want to change the rules by simple majority, more power to them. I think they would rue the day they did it. They’re not going to do that,” he said. 

The Senate is scheduled to begin voting on Tuesday to end debate on seven nominees, beginning with Cordray.

Republicans have blocked Cordray, even though he once clerked for conservative Judge Robert Bork, to demand reforms to the bureau, which was created by the 2010 Dodd-Frank Wall Street Reform Act. 

The Senate will then proceed to three of Obama’s nominees to the National Labor Relations Board: Richard Griffin Jr., Sharon Block and Mark Gaston Pearce. Republicans oppose Griffin and Block because Obama recess-appointed them to the board in January 2012, a move later ruled invalid by the D.C. Circuit Court of Appeals.

Sen. Tom Udall (D-N.M.), an outspoken proponent of Senate rules reform, predicted the votes will take place as scheduled.

Reid repeatedly called on Republicans during the meeting to vote with Democrats to end debate on Obama’s most controversial nominees to avoid a showdown over the rules.

“The leader kept asking for six Republicans. ‘We need six Republicans. We just need six Republicans. Six Republicans come with us, then that’s it. Then all these nominees can be approved.’ He said that’s the answer,” Harkin said.

If Republicans defeat a motion to end debate on Corday or the NLRB nominees, Reid could trigger the nuclear option at any point this week. A Democratic aide said the most likely option would be for him to make a point of order objecting to the filibuster of executive branch nominees when he calls up a motion to reconsider ending debate on Cordray or another of the blocked nominees.

Reid, however, has other procedural paths open to him.

McConnell said Sunday the crisis over changing the rules boils down to Cordray, Block and Griffin.

He has signaled that he will allow final votes on three of the seven pending nominees: Tom Perez, Obama’s choice to head the Labor Department; Gina McCarthy, the nominee to serve as administrator of the Environmental Protection Agency; and Fred Hochberg, who is slated to head the Export-Import Bank.

Durbin said the focus of negotiations have been on the consumer protection bureau and the labor relations board.

He dismissed the possibility that Democrats would agree to reforming the consumer protection bureau in exchange for Cordray’s confirmation.

“I don’t support that,” he said.

He also downplayed a Republican proposal to replace Block and Griffin as nominees to the NLRB.

“People have talked about that for quite some time, but this is not easy. This has been an agency that’s gone through troubled times because it’s very unpopular with some members of the business community and the Republican leadership,” he said. “The two people who are involved here, no one has suggested there’s anything wrong with them.”

This story was posted at 9:54 p.m. Monday and last updated at 10:17 a.m. Tuesday.