Though Pawlenty said in an interview with ABC News's Jon Karl that he hadn't seen the ad, he interpreted it as a swipe at Romney's wife, Ann, who has said she used horse-riding to cope with her illness.
"Well, I haven't seen the ad, but shame on them, really," Pawlenty said. "I mean, this is something that she does as a hobby to help her condition as a therapy for having MS, and it gives her great relief and great joy. And I think by her own account and the account of her medical professionals, it helps her. That's something she shared with others as a sport or hobby or therapy who are facing life challenges or disabilities, and to make light of that or to criticize that, I think, is really, really low. I wish they wouldn't do that."
Dressage is not just Ann Romney's passion but a hobby of Mitt Romney's as well. In a leaked video before an interview with Fox News that was lightly made fun of online, Romney told Sean Hannity about his various dressage horses.
"It is actually Ann's passion, not so much mine, to tell you the truth," he said.
In a statement, Melanie Roussell, a spokeswoman for the Democratic National Committee, which made the ads, said: "What Gov. Pawlenty is alleging is inaccurate and distracts from the main point. One of Mitt Romney's hobbies and investments is his dressage horse. And, like his horse, Mitt Romney continues to dance around the issues, from answering why he's invested in known foreign tax havens or trying to rewrite his position on letting Detroit go bankrupt."