Presidential hopeful Sen. Ted Cruz finally has the support of one of his colleagues — Sen. Mike Lee has endorsed him.

Politico reports:

Utah Sen. Mike Lee plans to endorse Texas Sen. Ted Cruz Thursday, making him the first U.S. senator to back Cruz’s presidential bid, sources told POLITICO.

In a blow to Florida Sen. Marco Rubio, whose campaign is on life support as he seeks to avoid a knock-out blow in his home state Tuesday, Lee is expected to make the announcement in Rubio’s hometown of Miami ahead of Thursday night’s GOP debate.

Lee is close with both senators, and he had resisted jumping into the race and potentially alienating one of them. He sat down with Rand Paul, Rubio and Cruz as the presidential campaign got underway one year ago and told them: “Look: I’m in an awkward spot because I’m really close to all three of you guys.”

“One of the weirdest things that can happen to a person is to have his three favorite co-workers all running for president of the United States at one time,” Lee said during a December interview. “It’s just weird.”

But that neutrality waned as Trump rose and Rubio faltered. With crucial primary votes in just five days, the chairman of the Senate GOP’s conservative Steering Committee still has a chance to make a difference in the race.

But it may come too late to make a difference, said Sen. Orrin Hatch of Utah, the most senior Republican senator.

“I don’t know that anyone’s one endorsement is going to make a difference unless somebody came back from the dead or something like that,” said Hatch, who has backed Jeb Bush and Rubio but seems to be warming to Cruz. “But I don’t think it’s going to hurt anybody. Any senator’s endorsement is important, and Mike’s would be important, too.”

Cruz’s office did not immediately respond to a request for comment. Lee’s office declined to comment.

Ahead of tonight’s debate and next week’s primaries, Lee’s endorsement could be a big boost to Sen. Cruz. Earlier this week, former presidential contender Carly Fiorina also endorsed Sen. Cruz.

Yesterday, talk radio show host Mark Levin, too, officially threw his support behind Ted Cruz.

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