Senate Majority Leader Harry Reid (D-Nev.) on Saturday night postponed a vote on his plan to raise the country’s debt ceiling, a move that suggests a compromise between congressional leaders and the White House aimed at averting a default Aug. 2 may be close at hand.

In remarks on the Senate floor at 10 p.m., Reid said that he’d spoken with the White House “quite a few times this evening” and announced that the Senate would vote on his reworked debt-ceiling bill at 1 p.m. Sunday.

“There can be no short-term agreement, and I’m now optimistic that there will be no short-term arrangement whatsoever,” Reid said, referring to one of the major sticking points between the parties in the debt-ceiling debate. Democrats have preferred a plan that would extend the debt ceiling through the November 2012 election, while Republicans have maintained that a proposal that would extend the debt ceiling in two stages would be the best path forward.

The Senate had originally been slated to vote on the Reid debt-limit plan at 1 a.m. Sunday.

Reid’s postponement of the vote – which comes as Senate Minority Leader Mitch McConnell (R-Ky.) has resumed discussions with the White House – means that the Senate will take up the debt-ceiling proposal two days ahead of an Aug. 2 deadline by which Congress must vote to raise the $14.3 trillion borrowing limit or else the country will default.

Reid cautioned Saturday night that “there are many elements to be finalized, and there is still a distance to go before any arrangement can be completed, but I believe we should give everyone as much room as possible to do their work.”

He added: “I’m glad to see this move toward cooperation and compromise. I hope it bears fruit.”

The Nevada Democrat’s statement was a marked shift from his tone earlier Saturday in a face-off on the Senate floor with McConnell.

During the floor debate, Reid criticized as “not true” Republicans’ claims that their debt talks with the White House were making progress toward an agreement. McConnell had shot back that “the only way that we’re going to get an agreement before Tuesday is to have an agreement with the president of the United States.”

Both parties are racing to work out an agreement before Tuesday’s deadline. Ideas on the outline of a deal were abundant Saturday night, but lawmakers said that a potential compromise could involve a “trigger” mechanism that would force a bipartisan committee of 12 lawmakers to act to identify further spending cuts before the end of the year.

The two sides appeared to remain at odds on whether such a trigger would include both spending cuts and tax increases – the option preferred by Democrats — or just spending cuts alone, the plan Republicans favor.

While Reid’s announcement paved the way for a potential compromise, some lawmakers were dissatisfied that a deal was apparently being worked out by a small group of leaders behind closed doors.

“As we delay voting in the Senate, we continue to see power consolidated into the hands of just a few legislative leaders,” freshman Sen. Mike Lee (R-Utah) said via Twitter. “This is troubling.”

On the Senate floor earlier Saturday, Sen. Rob Portman (R-Ohio), a former White House budget director who has been working closely with McConnell throughout the debt-limit discussions and has also been meeting with Senate Budget Committee Democrats, sketched out one option for a potential compromise.

Such a plan would include spending cuts commensurate with the increase in the debt ceiling – one of the debt-limit conditions put forth by House Speaker John Boehner (R-Ohio). Portman argued that a dollar-for-dollar proposal “makes sense for our economy” because it would not only enact short-term cuts but would also balance the federal budget within 10 years – something that even Rep. Paul Ryan’s (R-Wis.) fiscal 2012 budget would not achieve.

The potential compromise sketched out by Portman would also allow for a longer-term debt limit increase provided that “meaningful and credible spending cuts” were achieved – meaning that the savings in Reid’s proposal that would be achieved by winding down the wars in Iraq and Afghanistan would not be included in the dollar-for-dollar comparison.

Portman’s plan would also call for a vote on a balanced budget amendment to the Constitution. That would differ from Boehner’s reworked proposal, which would call for such an amendment to be passed by Congress before a second vote early next year to raise the debt ceiling would be allowed to take place.

This post has been updated since it was first published.