A Republican presidential candidate has not won Pennsylvania since Ronald Reagan in 1988, although the split demographics of the state — a strongly conservative area in the middle of the state bookended by heavily Democratic Pittsburgh and Philadelphia — leave the state's 20 electoral votes an enticing goal.

But while Romney pledged a November win in the Keystone State, he played down expectations for his upcoming primary against native son Rick Santorum.

"I think everybody expects someone to win their home state. Newt Gingrich won his state, I won my state. I think people expect the senator to win his home state. But I’ll pick up a lot of delegates, and we have several other states with contests the same day. I hope to win all of those. And if I can win the others and pick up some delegates here, it will give me a stronger lead," Romney said.

Romney also attacked the president as out of touch, saying the president lives in a "bubble in Washington, D.C., surrounded by people who love everything that comes out of his mouth" and saying "he spent too much time at Harvard, perhaps."

Democrats seized on the latter comment, pointing out that Romney spent more time — and has more degrees -— than Obama at the elite university.