Seamus has been fodder for Democrats for months, based on an old story of a Romney family vacation in the 1980s, when Seamus rode along on top of the car in a special carrier.
In Iowa, the president was criticizing the presumptive GOP nominee for not supporting tax credits for wind energy companies.
"During a speech a few months ago, Governor Romney even explained his energy policy this way -- I'm quoting here -- 'You can’t drive a car with a windmill on it,'" Obama said.
Then, he went on with the zinger: "Now, I don't know if he has actually tried that. I know he has had other things on his car."
The Romney campaign fired back.
"After sanctimoniously complaining about making a 'big election about small things,' President Obama continues to embarrass himself and diminish his office with his un-presidential behavior," spokesman Ryan Williams said.
The Seamus vacation incident was back in the 80s, but somehow still has popped up in the news cycle decades later.
Romney said in an interview with "Fox News Sunday's" Chris Wallace that Seamus "enjoyed" being up there, in his air-tight carrier with a custom-made windshield. Though in an interview with ABC, Romney said he probably would not do it again considering the attention it has received.
But dogs have also been a topic for Republicans, too, picking up on the fact that Obama noted in his book "Dreams From My Father" that he ate dog as a child.
Every campaign season has its peculiar and quirky themes, and apparently for 2012, it's dogs.