Ιf Romney had any class and wanted to show to Santorum that he respects him then he shouldn't contest Pennsylvania.
But we are talking about Romney here, a man who is unanimously hated be all the other 2008 and 2012 candidates.
lolwut. When was the last time a candidate chose not to contest a state that they otherwise had a strong chance of winning? And how is Romney so hated by his fellow candidates that he's been endorsed by at least four of them so far?
In 2004 neither Kerry, nor Edwards contested Vermont even though Howard Dean had already dropped out.
Exactly - Howard Dean had already dropped out, so it didn't matter too much if he won - it wasn't going to give him any momentum. However, Rick Santorum is still in the race and at least says that he can win. Winning Pennsylvania would probably give him the momentum to at least stay in until June. A loss in Pennsylvania could result in the end of his campaign, which would allow Romney to start fully focusing on Obama a month sooner.