Washington (CNN) Donald Trump is eager for Jeff Sessions to become his attorney general, but not a moment too late.

Trump is pushing his final Cabinet nominees through the Senate, including Sessions, but Republicans are staggering the confirmation votes to keep the Alabama senator in his seat for as long as they need him.

As soon as Sessions becomes the attorney general, he'll have to resign his Senate seat, creating a vacancy.

And for now, Republicans need his vote. After sitting out the confirmation process for his fellow Trump nominees, Sessions emerged Thursday to cast a key committee vote on behalf of Mick Mulvaney, the President's pick to run the Office of Management and Budget. The Senate Budget Committee only has a one-vote GOP majority so if Sessions sat out, Republicans wouldn't have had to votes to advance Mulvaney's nomination.

Sessions will be needed once more when the fate of Betsy DeVos, Trump's pick for education secretary, is decided on the floor of the Senate.

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