Rubio: Debates Are About Informing, Not Entertaining

Luntz Focus Group Thought This Rubio Moment Was the Best of the Night

Marco Rubio acknowledged that his personal attacks on Donald Trump were "not something I'm entirely proud of."

"My kids were embarrassed by it, and if I had to do it again I wouldn't," Rubio said in an interview Wednesday, regretting that he went after the Republican presidential front-runner's age, appearance, spelling and even hand size.

On "Outnumbered" today, Andrea Tantaros noted that those attacks weren't only embarrassing for Rubio, but they also failed to help the flailing Florida senator gain traction in the 2016 race.

She said it's an important lesson for Rubio: "Be yourself."

Tantaros explained that he went so negative that he "sandbagged himself," in a glaring example of what bad advice can do to a presidential candidate.

Watch more from "Outnumbered" above.

Rubio on Islam: 'I'm Interested in Being Correct, Not Politically Correct'

'I Don't Have to Be Politically Correct': Trump Doubles Down on 'Islam Hates Us'

Rubio on Climate Change: 'It's Always Been Changing; America's Not a Planet'

Carson Endorses Trump: 'It's Not About Me or Mr. Trump, It's About America'