Almost everyone has conceded that Romney will be the nominee, but not R.S. McCain:

Yet such is the pressure now to unite Republicans behind Mitt’s moderate banner that Tuesday night on Fox News, Krauthammer argued that Santorum should quit even before the April 24 primary in his home state of Pennsylvania.

That was perhaps predictable, too, because Krauthammer and the other Fox News panelists surely know that if Santorum can manage to win Pennsylvania and fight on into May, the inevitable Romney may not be as inevitable as some pundits have predicted.

As I don’t care much for Santorum or Romney, I have no objection to Santorum’s staying in for as long as he wants. The longer he remains in, the more of a distraction it will be for Romney, and the worse it will be for Santorum’s hopes of attempting another run in four years. If there is one thing that would be worse for the eventual nominee than a protracted internecine feud, it is a feud that is completely futile and won’t change the ultimate outcome. Continuing to campaign might make sense for Santorum if there were that many meaningful differences between him and Romney, but there simply aren’t very many. The GOP is not facing a choice between dramatically different directions. If the party did nominate Santorum, it would be an endorsement of a Bush-era big-government warmonger, and when it nominates Romney it will be an endorsement of someone who essentially accepts the entire Bush-era agenda (except for immigration policy) and wants to repeat it. The most meaningful difference between them is that one is an ideologue and the other is a liar. More Republicans seem to prefer the liar.