It happened on Mark Levin’s video podcast tonight. Via Conservative Review…

On tonight’s episode of LevinTV Senator Marco Rubio (R-FL) joined Mark Levin in a wide ranging interview. The two touched on a host of topics, including Rubio’s future political plans, his foreign policy vision, and who he thinks should be the president. When Levin asked Rubio who he would be supporting for the corner office, Rubio said that his delegates are bound on the first ballot. He added that on subsequent ballots, “I hope that they’ll nominate a conservative.” Rubio added, “the only one[presidential candidate] that fits that criteria is Ted Cruz.” Recently Rubio made it clear to state Republican parties that he has not withdrawn from the race completely. He did that in order to ensure that every one of his delegates was bound to him on the first ballot of an open convention. Most state GOP officials have complied with his wishes. Tonight was the first time that Rubio has made it clear that he would support Cruz on a second ballot, of all the candidates remaining.

Rubio has hinted at a Cruz endorsement for a while, but hasn’t quite gone there yet. Even this isn’t what you’d call an official endorsement – he can’t really make one if he’s going to hold his delegates. This is as explicit as you’ll get until the convention.

Is it a big deal? It’s a pretty big deal. It shows that little by little, Cruz is stitching together the disparate elements of the Republican coalition. With Rubio making such a public case for Cruz, he’d likely be making a private case for him as well – and that potentially carries some support among people who really, really would rather not have to back Cruz.

That it happens only a few hours after Donald Trump mentioned that he likes Rubio as a potential vice-presidential pick adds a little flavor and irony to the proceedings.