One of former Pennsylvania Rick Santorum’s biggest stumbles in last week’s debate? Saying he voted for No Child Left Behind to “take one for the team.”

Now former Massachusetts governor Mitt Romney is using the words in a tough new ad.

The ad is airing in Ohio, a must-win state for both candidates, where Romney has bought $809,501 of air time this week.

The ad actually focuses on Title X spending — some of which funds Planned Parenthood — another issue on which Santorum got lost in the weeds of Senate procedure.

“I have a personal more objection to it, even though I don’t support it, that I voted for bills that included it,” Santorum is quoted as saying.

“Rick does this a lot,” the narrator ads, and then cuts to his defense of his vote on education reform: “It was against the principles I believed, but you know, when you’re part of the team, sometimes you take one for the team.”

The ad concludes: “Rick Santorum: Just another Washington insider.”

It’s a pretty negative spot for the campaign to run; so far this cycle, these kinds of attacks have mostly been handled by the independent super PACs. And in fact, the pro-Romney super PAC Restore Our Future is running a similar ad: