WASHINGTON ― Colin Kahl, nominated for the Pentagon’s undersecretary for policy, remains stalled at the Senate Armed Services Committee, but even if he clears it, he could well face a gauntlet of tough votes toward confirmation by the 50-50 Senate.

Nearly two weeks after Kahl’s confirmation hearing, the panel has held off scheduling a vote on whether to advance the nomination to the floor, forgoing a major test of whether Kahl has enough support to win confirmation in the Senate and President Joe Biden’s clout in Congress.

If confirmed, the former national security advisor to then-Vice President Biden would be the Pentagon’s No. 3 civilian, overseeing the Defense Department’s policy shop, including its strategy, nuclear deterrence, missile defense and international cooperation plans and policies. But close observers say the role is unlikely to be filled before May because of Kahl’s rocky confirmation process and the Senate’s busy calendar before its two-week recess March 29.

Kahl, who encountered pointed questions from Republicans for his Mideast policy positions and history of tweets attacking Republicans, faces solidifying opposition after SASC’s influential top Republican, Sen. Jim Inhofe, told Politico that he wouldn’t support the nomination. Democrats have largely refuted the depiction of Kahl as hyper-partisan, and Biden has stood behind him.

Democrats in the evenly divided Senate can confirm Biden’s nominees without any Republican votes, but they have to unify and have Vice President Kamala Harris cast a tie-breaking vote. If Kahl makes it out of committee, Biden and Democratic leaders would still have to juggle Kahl’s tricky nomination with their legislative agenda and ten nominees already on the Senate’s executive calendar.

“It’s up to the Biden administration whether they want to go to the mat, but it’s all doable,” said Jim Manley, who was a senior aide to then-Senate Majority Leader Harry Reid, D-Nev. “I personally would hope that if there’s an obstacle the White House figures out a way to go around it, but that’s difficult in a narrowly divided Senate.”

The smoothest path for Kahl would be a majority in the evenly-divided, 26-member SASC. But that’s uncertain amid Republican opposition and wavering from West Virginia Democratic Sen. Joe Manchin ― a potential swing vote on the committee and in the Senate ― who said publicly he is undecided, even after speaking with Defense Secretary Lloyd Austin last week.

The White House pulled Biden’s first nominee for budget director, Neera Tanden, amid opposition from Manchin and Republicans over her caustic online criticism of lawmakers. Like Tanden, Kahl has apologized for his “sometimes disrespectful” remarks on social media, pledging to serve in a nonpartisan fashion if confirmed.

Outside the Armed Services committee, where Inhofe and four others oppose Kahl, Sens. Marco Rubio, R-Fla., and Shelly Moore Capito, R-W.Va., announced their opposition last week. Rubio said Kahl’s “hateful and unhinged rhetoric toward our fellow Americans is the exact opposite” of Biden’s campaign pledges to unify the country.

Some Democrats have claimed a double standard. “This is again another example of Republicans complaining about mean tweets, and yet, these same Republicans never criticized [President Donald Trump] for all the outrageous invective and/or racist rhetoric he spewed on Twitter 24 hours a day,” Manley said.

If the SASC splits evenly between Republicans and Democrats, Senate Majority Leader Chuck Schumer, D-N.Y., would have to file a discharge petition to advance the nomination to the floor.

From there, Republicans could obstruct Kahl’s nomination, which would mean he’d face as many as four Senate floor votes: a cloture vote on the discharge petition, a vote on the petition itself, a cloture vote on his nomination and a vote on the nomination itself.

Manley suggested Senate Foreign Relations Committee Chairman Bob Menendez, a New Jersey Democrat who bucked Democratic President Barack Obama to oppose the 2015 Iran nuclear deal would be one lawmaker to watch because of Kahl’s long record of vocal advocacy for the deal. (Menendez hasn’t taken a public position on Kahl’s nomination.)

When Defense Secretary Chuck Hagel ― the only nominee for defense secretary to be filibustered ― stepped down in 2014, his troubled tenure was blamed on a bruising confirmation process and his alienation from the White House. Would Kahl emerge hobbled by a narrow confirmation?

James Miller, who served as an undersecretary of defense for policy under Hagel, said Kahl’s effectiveness, if confirmed, is assured by Kahl’s ties to Biden and his close work with Austin when Kahl led Mideast policy for DoD and Austin was U.S. Central Command chief.

“Colin has the most important thing for the undersecretary of policy, which is the complete trust of the secretary of defense,” Miller said. “The folks in uniform will see he had a close vote and wonder if he’s not as powerful, but what matters for anyone in OSD, particularly on the policy side, is the backing of the SecDef.”

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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