WASHINGTON - Senate Republicans' reservations about one of their own heading the Pentagon are caught up in potent politics, from a proxy fight over President Barack Obama to more parochial concerns about nuclear weapons facilities.
Former Sen. Chuck Hagel, Obama's choice to be his new defense secretary, has reached out to all 100 senators and will be meeting personally with dozens of them starting this week, according to an official working on his confirmation.
The sessions - and, more importantly, what Hagel says - will be vital for a nomination that faces outright opposition from a handful of Republicans, including the second-ranking Republican, Sen. John Cornyn of Texas; nervous questions from influential Democrats such as New York Sen. Chuck Schumer; and plenty of non-committal senators.
Hagel's very public confirmation hearing before the Armed Services Committee will probably occur within weeks.
The official was not authorized to speak publicly on the matter and spoke on condition of anonymity.
The nominee enters the make-or-break period with critical support - former Secretary of State Colin Powell called Hagel "superbly qualified," and Armed Services Chairman Carl Levin, D-Mich., and Intelligence panel chairwoman Dianne Feinstein, D-Calif., have praised Hagel's extensive knowledge of national security issues.
Sen. Barbara Boxer, D-Calif., a senior member of the Foreign Relations Committee, said late Monday that she would support Hagel's nomination. She said he provided answers to a range of questions and promised to support Obama's policies "without reservation."
The former Nebraska GOP senator has been dogged by questions of whether he's soft on Iran, weak in his backing for Israel and opposed to gay rights.
"A lot of charges rise up and fall when the facts are presented," Sen. Jack Reed, D-R.I., a friend of Hagel's, said in an interview Monday. "That's the same thing that's going to happen here. These claims - suddenly claims are debunked - and we get on to substance."
Backers of Hagel's nomination counter criticism by pointing to his votes for some $40 billion in military and security aid for Israel during his 12 years in the Senate and his support for all options, including military action, to prevent Iran from developing a nuclear weapon. They argue that his position on gay rights has evolved.
Despite the support, Hagel - a Republican tapped by a Democratic president - has few advocates in either party in the Senate and a limited number of opportunities to make inroads with the GOP.
A potential vote is Sen. Bob Corker, top Republican on the Foreign Relations Committee, who served two years with Hagel and has spoken highly of him. But the Tennessee lawmaker has real reservations about Hagel's views on nuclear weapons, which could affect more than 5,000 jobs at the Y-12 National Security Complex near Oak Ridge, Tenn.
Any cuts in the nation's nuclear arsenal would affect work at the Y-12 nuclear weapons plant, which makes uranium parts for every warhead and is the primary storehouse for bomb-grade uranium. The facility also dismantles old weapons.
Corker was one of the few Republican votes in December 2010 for a new U.S.-Russia treaty on reducing the number of nuclear weapons and establishing a verification process.
"A lot of modernization was supposed to take place as a result of that on our nuclear arsenal. That's not happening at the pace that it should. The Pentagon is going to have a big effect on that, and for me, that is going to be a very big issue," the senator said Sunday in an interview on ABC's "This Week."
Corker also raised questions about Hagel's "overall temperament" for the job, citing unidentified former staffers. Questions to Corker's office Monday about the staffers went unanswered.
In May, Hagel was one of the authors of a report that called for an 80 percent reduction of U.S. nuclear weapons and elimination of all nuclear-armed intercontinental ballistic missiles, a step that would have a clear impact on Corker's home state.
The study for the advocacy group Global Zero argued that the United States needed no more than 900 total nuclear weapons for its security in a post-Cold War era. The U.S. and Russia have an estimated 5,000 nuclear weapons each, either deployed or in reserve. The two countries are already on track to reduce to 1,550 deployed strategic warheads by 2018, as required by the New START treaty.
The Obama administration reportedly is considering various options for lower total numbers of deployed strategic nuclear weapons. The report calls for such weapons to be reduced to about 450, while maintaining an equal number of stored weapons.
"There is no conceivable situation in the contemporary world in which it would be in either country's national security interest to initiate a nuclear attack against the other side," the report said.
Joining Hagel on the report was retired Gen. James Cartwright, the former vice chairman of the Joint Chiefs of Staff; former ambassadors Richard Burt and Thomas Pickering; and retired Gen. Jack Sheehan.
Backers of Hagel's nomination insist that he supports a strong and ready nuclear arsenal.
Even though the 2014 midterm elections are months away, some Senate Republicans are nervously watching for tea party challenges and determined to avoid them at all costs. Opposition to any Obama nominee will be a requirement for conservative voters. Republicans looking to head off any threat from the far right are Georgia's Saxby Chambliss, South Carolina's Lindsey Graham and Texas' Cornyn.
Democrats hold a 55-45 advantage in the Senate, and the party has the numbers to confirm Hagel if the vote is a simple majority. A possible Republican filibuster and a threshold of 60 votes would add even more rancor to the current fight between Democrats and Republicans over Senate rules just as the leaders are trying to negotiate a compromise.
Sen. John McCain, R-Ariz., will have plenty of sway with some of his colleagues even though Sen. Jim Inhofe, R-Okla., has replaced McCain as the top Republican on Armed Services due to GOP term limits. McCain and Hagel once worked closely together, but differences over the Iraq war and the 2008 presidential election have pushed the two apart.
McCain, who has talked about presidents having the chance to choose their Cabinet, has said he has significant questions about Hagel's nomination.
Said Democrat Reed of the fierce Senate process, "Unfortunately everything is getting to be like a Supreme Court pick."
Associated Press writer Erik Schelzig in Nashville, Tenn., contributed to this report.