Is Romney a Liberal?

Hello readers,
In my opinion, which most people have agreed, Romney has done really well in the debate yesterday. Santorum, however, did not seem to do as well so he is planning to recover and while he is doing that, he is going to prove that his opponent is a liberal. What! That's not cool? Gingrich seemed to overly accuse it Romney for many things instead of supporting himself; isn't that why he is not in 2nd place anymore?
http://abcnews.go.com/blogs/politics/2012/02/rick-santorum-previews-fresh-attack-on-mitt-romney-hes-resolutely-liberal/