With a very limited campaign war chest and almost no infrastructure and ground game, Santorum ultimately emerged as Mitt Romney's major rival for the Republican nomination. Many thought Romney would have stronger challenges from Rick Perry or Tim Pawlenty. Not the case.

Santorum was a surprise success. He won more states than Mike Huckabee and the same amount of states Romney won four years ago in challenging Sen. John McCain. Santorum could be a major force in the 2016 Republican presidential contest should Romney fail to unseat President Barack Obama in November. While he would face the likes of Chris Christie, Bob McDonnell, Marco Rubio or Mitch Daniels, Santorum has already proven he can appeal to the solid bloc of social conservatives within the GOP.

It could even be argued that Santorum was able to repair some of the heavy political damage he sustained after Robert Casey trounced him by 18 percentage points in his failed 2006 Senate re-election contest. While Santorum cannot run away from this absolute drubbing, he can now claim that as an underdog he threatened to derail Romney's establishment-backed campaign. Among donors, media pundits and social conservatives, Santorum succeeded in raising his profile in Republican Party politics.

Quite ironically, the only problem facing Santorum right now is a possible poor showing in Pennsylvania. Should Santorum fail to win Pennsylvania, he will lose the political capital he built in framing himself as the conservative alternative to Romney. A recent poll suggests he is clinging to a six-point lead. A loss would be another embarrassing defeat in his home state.

If Santorum is able to win Pennsylvania, he could make a strong case to stay in the race and press for a major showing at the Republican convention in Tampa, Fla. However, this could backfire on him. While a win certainly would position him for 2016 or 2020, his attacks will harm Romney's chances of building a united front against Obama. Santorum risks not being remembered as an underdog who took on the Republican establishment, but a self-serving politician who put himself above his party by damaging the credibility of the inevitable nominee.

By staying in the race, is Santorum doing more harm to Romney and the Republican Party or is he simply making a strong case for 2016 and beyond?

Chris Dolan is associate professor of political science at Lebanon Valley College and the author of “Striking First,” “In War We Trust” and “The Presidency and Economic Policy.”