That is complete barbra streisand and you know it. Conservatives didn't punish Santorum for supporting Specter by staying home on election day. The liberals and the democrat vote fraud machine in Philly and Pittsburgh turned out in full force. Squishy independents/undecideds leaned toward Casey, who ran as a conservative democrat.
I'm just repeating in jest what many people on this site said at the time: that they could not forgive Santorum for supporting Specter. I don't necessarily agree with that argument, since I place Santorum's lose at the feet of the media for their numerous manufactured scandals which pushed the independents towards Casey.