It's quite possibly the most egregious Reagan Rule violation by a primary challenger ever, is what it is. And coming from the same guy who made this appeal just 4 years ago:
"In a few short days, Republicans from across this country will decide more than their party's nominee. They will decide the very future of our party and the conservative coalition that Ronald Reagan built. Conservatives can no longer afford to stand on the sidelines in this election, and Governor Romney is the candidate who will stand up for the conservative principles that we hold dear," said Senator Santorum. "Governor Romney has a deep understanding of the important issues confronting our country today, and he is the clear conservative candidate that can go into the general election with a united Republican party."
So let's see...Mittens hasn't held office in 4 years, nor done much other than operate Bain Capital, so somehow in that time, Obama has improved enough in Santorum's standing that we might as well "stay with what we have" over the "clear conservative candidate".
This isn't a Jump The Shark moment for Santorum, it's a Shark Meat moment, because Ricky didn't clear the tank....