On Tuesday, the Senate confirmed Sen. Chuck Hagel as the newest Secretary of Defense, replacing outgoing Secretary Leon Panetta. The vote ultimately came down to the affirmative votes of four key Republican senators: Thad Cochran (Miss.), Mike Johanns (Neb.), Richard Shelby (Ala.), and Rand Paul (Ky.).

Although Paul had previously been an outspoken critic of Hagel, he earlier explained his vote for confirmation, and reminded critics that presidential appointees are Obama’s “prerogative”:

“I voted for John Kerry and I agree with nothing he represents,” he said, “but I voted for him because I thought there was a level of at least basic human decency and honesty that exists there … and that the president has the prerogative to determine political appointees.” …

He went on, “I would never vote for him in an election so I saw it a little bit differently. I see Hagel and [CIA nominee John] Brennan and [Treasury nominee Jack] Lew kind of the same way. I don’t agree with much of their policies with any of them … They’re going to be Obama appointees … On Hagel, there’s criticims of both on the conservative right there’s also criticism on the libertarian right.”

Paul said Hagel is “not a small government libertarian” and added, “There are reasons to vote against him … and I did vote against cloture … [but] I haven’t yet decided on final passage. To me right now, and I know people are hot and heavy on the Hagel thing — I’m more hot and heavy on the Brennan thing.”

Many conservatives were upset with Paul’s change-of-heart and Twitchy captured some of their reactions to the vote on Twitter:

For more reaction, tune in Thursday when Sen. Paul talks with Glenn on radio.