Pennsylvania Primary, Republican Presidential Candidate | featured news

Five states are set to hold primaries in the race for the Republican nomination Tuesday, including Pennsylvania and New York, but Mitt Romney won't be spending his election night in any one of them.

Republican presidential candidate Rick Santorum, in what may be a grim development for his campaign, has lost the lead in his home state of Pennsylvania to front-runner Mitt Romney, according to a poll released on Thursday.

The Rick Santorum campaign is formally calling on Newt Gingrich to drop out of the race and endorse the former Pennsylvania senator, following Tuesday night's three-primary sweep by Mitt Romney. Santorum's communications director Hogan Gidley made the statement during a Wednesday appearance on MSNBC.

The former Pa. senator leads among likely GOP voters back home, but nearly 4 in 10 could change their minds before the April 24 primary.