Updated 11/18/2016 9:00 AM Eastern to reflect the announcement of Sessions for Attorney General.

WASHINGTON — Former Missouri Sen. Jim Talent is the front-runner to be the next defense secretary under President-elect Donald Trump, according to a source close to the matter.

The 60-year-old Talent, who served for 12 years in the House and the Senate, would represent a more traditional wing of the Republican national security apparatus, and his nomination could calm fears that Trump will staff his top tier of advisers only with loyalists.

With the Trump transition team, nothing is certain until it is announced. Amid negative reports of chaos and leadership shakeups within Team Trump transition​, rumors and speculation have surrounded the selection process for Cabinet secretaries, with at least a half-dozen names alone mentioned for defense secretary in the last week.

Trump himself sent a defiant tweet on Tuesday: "Very organized process taking place as I decide on Cabinet and many other positions. I am the only one who knows who the finalists are!

Sen. Jeff Sessions, Trump's adviser, ally and a voice on his defense policy, appeared to be the likely pick for the Pentagon job as recently as Wednesday. However, that talk cooled Thursday morning as it seemed more likely he would be nominated for the role of US attorney general -- a move that become official early Friday, when Trump announced Sessions was his pick for AG.  It is a job that Sessions may have coveted for years, ever since his bid for a federal judge position in 1986 was foiled under allegations of racism. Sessions narrowly was denied confirmation, but returned to the Senate victorious following a 1996 election.

In addition to Sessions, Trump made a surprise announcement by nominating Rep. Mike Pompeo (R-Kansas) as CIA director. He also confirmed the expected move of naming retired Lt. Gen. Michael Flynn, the former chief of the Defense Intelligence Agency, as his National Security Advisor.

The Trump insider, someone who has provided national security advice to the transition, said Sessions, for his loyalty and support to Trump, could have chosen any job he wanted within the new administration. But given Sessions' interest in combating illegal immigration, he apparently prefered to be US attorney general for a president who made a big issue of restricting immigration and refugees.

"He would be great at a lot of different things," the insider said. "He's a big picture guy on defense, not someone sitting in the minutia of procurement. … I don't see him wanting to deal with cruiser modernization and all the stuff you do day-to-day in the defense secretary job."

For Talent, by contrast, the DoD job would likely be his sole focus.

One source familiar with Talent agreed that his stock appeared to be rising, calling it an unambiguously good thing for the Pentagon.

The source compared Talent to Michele Flournoy, the Center for a New American Security head and former policy lead at the Pentagon who was widely expected to be named defense secretary had Hillary Clinton won the presidency, saying Talent is "incredibly prepared" to hit the ground running.

The timing of Talent's rise coincides with reports that former Massachusetts Gov. Mitt Romney will be meeting with Trump on Sunday and is being considered for secretary of state. Talent and Romney are "extremely" close, and the two would be able to work well together, the source said.

Another key advantage for Trump is Talent's ties to a number of GOP think tanks and scholars. One organization to watch: The American Enterprise Institute, where Talent directs the National Security 2020 project.

A number of conservative scholars from AEI and elsewhere were part of the "never Trump" movement, and signed a letter opposing candidate Trump over the summer. If Talent was named defense secretary, some of those individuals may agree to work for him, filling out the crucial mid-tier jobs that the Trump team is expected to struggle with.

Fifty national security officials from GOP administrations, in a letter made public in August, said Trump would be a "dangerous" president and "lacks the character, values, and experience" for the job. Thirty former Republican members of Congress released a letter in October saying they cannot vote for Trump because he "makes a mockery" of their principles.

Talent, according to the Trump campaign source, rejected a chance to sign a letter supporting Trump, but he did not sign a letter condemning Trump either.

"There will be a sliding scale, where if you didn't endorse him, fine," the Trump adviser. "If you signed a letter that called Trump a xenophobic, racist, fascist, like so many people did, you're not going to get a job."

Email:  jgould@defensenews.com |  amehta@defensenews.com

Twitter: @ReporterJoe | @AaronMehta

Aaron Mehta was deputy editor and senior Pentagon correspondent for Defense News, covering policy, strategy and acquisition at the highest levels of the Defense Department and its international partners.

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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