WASHINGTON (AP) — Chuck Hagel — twice-wounded Vietnam combat veteran and former Republican senator — faces his first major hurdle in his bid to become US defense secretary as a bitterly divided Senate Armed Services Committee pushes toward a vote on his nomination.

The panel is scheduled to meet Tuesday to vote on President Barack Obama’s choice to succeed Defense Secretary Leon Panetta, who is stepping down after four years as CIA director and Pentagon chief. Senate Majority Leader Harry Reid, a Democrat, is pressing for a full Senate vote later this week.

Hagel faces fierce opposition from fellow Republicans who have challenged his past statements and votes on Israel, Iran, Iraq and nuclear weapons. When he was in the Senate Hagel often parted ways with his party to take an independent stand.

Just hours before the vote, foes circulated a memo arguing for more information about Hagel’s personal finances and highlighting past statements by Democratic senators demanding further disclosures when the Senate considered nominees by Republican presidents.

Committee Republicans forced a delay in the expected vote last week when they pressed Hagel for further data.

The panel’s chairman, Sen. Carl Levin, a Democrat, said the Republican demands were beyond the scope of those traditionally asked of previous nominees, Republican and Democrat — a point echoed by his Republican colleague, Sen. John McCain. Levin set a committee vote that will probably break along party lines — 14 Democrats for Hagel, 12 Republicans against their former colleague — just hours before Obama’s State of the Union address to Congress.

More critical to whether Republicans drag out the nomination is the closed-door weekly Republican luncheon Tuesday where Senate Minority Leader Mitch McConnell will determine whether Republican lawmakers have the inclination and votes to use Senate procedural rules to block a vote on a president’s Cabinet choice. Such a move would be unprecedented in the Senate, where Republicans and Democrats have argued that a president’s nominee should get a yes or no vote.

If Hagel is approved in committee, as expected, he faces Republican delaying tactics in the full Senate, with the panel’s ranking Republican, Sen. Jim Inhofe insisting that any confirmation be based on 60 votes rather than a majority of the 100-nember Senate.

But that effort has divided Republicans, with several longtime members opposed to the unprecedented step of delaying a president’s Cabinet nominee for defense secretary. The delaying tactics are known as a filibuster.

Late Monday, McCain met privately with several committee Republicans and urged them not to stall the Hagel nomination, pointing out that the roles could be reversed someday with a Republican president and Republican-controlled Senate.

“I’m encouraging my colleagues if they want to vote against Sen. Hagel that’s one thing and that’s a principled stand,” McCain told a group of reporters. “We do not want to filibuster. We have not filibustered a Cabinet appointee in the past and I believe that we should move forward with his nomination, bring it to the floor and vote up or down.”

McCain has not said how he would vote on the nomination, but has indicated he was learning against confirmation.

All 55 Democrats are expected to back Hagel, and two Republicans — Sens. Thad Cochran and Mike Johanns — have said they will vote for the nominee. At least five Republicans, including McCain, have said they oppose a filibuster despite their reservations or opposition toward the nominee.

More than a dozen Republicans have said they will oppose their former colleague, and several others have indicated they are likely to vote no. Sen. Kelly Ayotte, a Republican member of the Armed Services Committee, said Tuesday she would vote against the nominee, citing his performance at his confirmation hearing.

Hagel seemed ill-prepared under withering cross-examination from committee Republicans in nearly eight hours of testimony on Jan. 31. He was repeatedly pressed about past statements and votes on Israel, Iran and nuclear weapons, with Republican lawmakers suggesting he wasn’t sufficiently supportive of Israel or anti-Iran.

In the memo, Republicans focused on the 2005 fight over President George W. Bush’s nomination of John Bolton to be ambassador to the United Nations, and Democrats who tried to stop the nomination. The position is not Cabinet-level, however.

Faced with a Democratic filibuster, Bush circumvented the Senate and made Bolton a recess appointment.

Sen. Lindsey Graham, a Republican, has signaled that he would block the nominations of Hagel and CIA Director-designate John Brennan if he doesn’t get more answers about the deadly raid on the US diplomatic mission in Benghazi, Libya, last September.

“I’m insisting that the president answer … what he did that night. That’s all. It would take five minutes to answer my question,” Graham told reporters. “It’s the only leverage I have.”

The White House pushed back Monday, with spokesman Jay Carney insisting the administration had answered lingering questions about Libya and the president’s actions on that fateful day.

“What is unfortunate here is the continuing attempt to politicize an issue, in this case through nominees that themselves had nothing to do with Benghazi, and to do so in a way that only does harm to our national security interests,” Carney said. “Sen. Hagel, Mr. Brennan, they need to be confirmed.”

Copyright 2013 The Associated Press.