Only four Republicans crossed party lines on Tuesday to approve President Barack Obama's defense secretary nominee Chuck Hagel, but no senator sparked more confusion than Kentucky's Rand Paul, a vocal critic of Hagel who nonetheless cast his vote in favor of the former Nebraska senator.

Just hours after he had voted against a procedural measure to end debate over Hagel's nomination, Paul offered his support for Hagel's confirmation. Paul's spokeswoman explained that the senator decided to support Hagel because he believes that presidents should get "some leeway" on political appointments, an opinion he has been open about in the past.

"In the run-up to tonight’s vote to confirm former Sen. Hagel as secretary of defense, Sen. Paul voted twice against cloture on the nomination, because he agreed with many of his colleagues that there were questions that needed to be answered about the president’s nominee," Paul spokeswoman Moira Bagley told Yahoo News. "As he has said before, the president should be entitled to some leeway on his political appointments. That is why Sen. Paul voted in favor of Sen. John Kerry, with whom he largely disagrees on foreign policy, to serve as secretary of state, and that is why he voted for final passage of the nomination of Sen. Hagel this evening, with whom he also disagrees on a number of issues."

The Senate voted 58-41 to confirm Hagel, ending a long and contentious nomination process. The other Republicans who supported Hagel were Sens. Thad Cochran of Mississippi, Mike Johanns of Nebraska and Richard Shelby of Alabama.