Updated

Senate Democrats are plowing ahead with a committee vote on Chuck Hagel's nomination to lead the Pentagon, despite Republican demands for more financial information from the nominee and threats by one prominent lawmaker to hold it up over questions about Benghazi.

Sen. Carl Levin, chairman of the Armed Services Committee, said in a brief statement that the panel would meet Tuesday with the "intention to vote on the nomination after the members have an opportunity for discussion." Levin had postponed a vote late last week amid complaints from Republicans.

But over the weekend, more complications emerged. After top Defense Department officials testified at a separate hearing last week that President Obama only had one conversation with them during the night of the Libya terror attack, Sen. Lindsey Graham, R-S.C., said Sunday that the Senate should not allow Hagel to be confirmed "until the White House gives us an accounting" of that night.

"No confirmation without information," he said on CBS' "Face the Nation."

White House Press Secretary Jay Carney, though, voiced confidence that Hagel would be confirmed.

"Since his hearing, we have seen an increase in the number of senators who have come out and said that they will vote to confirm him," Carney said.

He described the evolving demands over Benghazi as Republicans "moving the goalposts yet again." He said the administration already agreed to have former Secretary of State Hillary Clinton and Defense Secretary Leon Panetta testify -- it was Panetta's testimony that prompted the additional questions from Graham about Obama's activities the night of Sept. 11, 2012.

Sources say that if the committee clears Hagel, the full Senate could vote as early as Wednesday.

Levin's opposition to Republican calls for more of Hagel's personal finances and his intent to hold a vote got an endorsement Monday from the panel's former top Republican -- Sen. John McCain.

The Arizona lawmaker said in a statement on Monday that Hagel had fulfilled the panel's rigorous requirements on information and a vote should occur. McCain said he still had concerns about Hagel's national security positions and declined to say how he would vote.

"I believe it is appropriate for the Armed Services Committee to vote on Senator Hagel's nomination and determine whether to move this nomination to the Senate floor where members can debate and express their own judgments on Senator Hagel," said McCain, who also rejected any GOP protest of the vote. "I will not participate in any walkout of tomorrow's committee vote -- an action that would be disrespectful to Chairman Levin and at odds with the best traditions of the Senate Armed Services Committee."

Obama tapped Hagel, 66, a former two-term Nebraska Republican senator and twice-wounded combat veteran in Vietnam, to succeed Panetta, who is stepping down after serving as CIA director and Pentagon chief in the president's first term.

Democrats hold a 14-12 edge on the Armed Services panel and it's likely that Hagel will win approval on a party-line vote just hours before Obama delivers his State of the Union address at the Capitol.

But Congress is deeply divided over the nominee, with Democrats backing the president's choice and Republicans pressing for more information about Hagel's finances and foreign donors to organizations that he has been affiliated with since leaving the Senate in 2009.

Two Republicans on the committee -- Sens. Jim Inhofe of Oklahoma and Graham -- have threatened to use their power to stop the nomination.

"I would threaten to cause a 60-vote margin; yes I would. If it took a filibuster, I'd do it that way," Inhofe, the top Republican on the committee, told "Fox News" on Sunday. Graham signaled that he would hold up Senate confirmation of Hagel and CIA Director-designate John Brennan if he doesn't get more answers about the fatal assault on the U.S. diplomatic mission in Benghazi, Libya, last month.

Ambassador Chris Stevens and three other Americans were killed in the Sept. 11 attack.

"We're going to get to the bottom of Benghazi," Graham said on "Face the Nation."

All 55 Democrats are expected to back Hagel and two Republicans -- Sens. Thad Cochran of Mississippi and Mike Johanns of Nebraska -- have said they will vote for the nominee.

The Associated Press contributed to this report.