Marco Rubio took the main stage at the Conservative Political Action Conference (CPAC) shortly after noon today and was met by a fawning packed house.
The crowd roared when he came out. It roared when, before taking questions from CNN's Dana Bash, he held up a bottle of water and asked her to hang on while he took a drink. It roared when he defended the Second Amendment and said that a belief in an all-powerful God is necessary to make sense of America's founding.
But his longest, loudest applause line of the appearance was a clear dig on front-runner Donald Trump. "I won't let the movement be hijacked by someone who's not a conservative!" he said. The statement was met with a prolonged standing ovation and enthusiastic cheering.
"Being a conservative can never be about how loud you're willing to scream, how angry you're willing to be, or how many names you're willing to call people," he said earlier in the speech. He also noted that Trump had backed out of speaking at the event, adding that that isn't particularly surprising since, last time he checked, CPAC "is for conservatives."
When Bash suggested that Rubio had stooped to Trump's level by talking about the size of the reality TV star's hands on the campaign trail, Rubio pushed back, saying that when a bully continues to punch innocent people, eventually someone needs to step up and punch him back. (The crowd loved that, too.)
The CPAC straw poll closed before he went on, and the results won't be announced until later this afternoon—but if the reaction to his appearance gives us a clue, Rubio's chances look good.
UPDATE 2/6/16: Cruz won the straw poll with 40 percent to Rubio's 30 percent and Trump's 15 percent. Also interesting: Two-thirds of participants described themselves as "a classical Reagan conservative" (no suprise there), while 28 percent chose "a libertarian conservative."