The New Yorker’s endorsement of Barack Obama contains a succinct description of the reason for my now-dislike for McCain:

Since the 2004 election, however, McCain has moved remorselessly rightward in his quest for the Republican nomination. He paid obeisance to Jerry Falwell and preachers of his ilk. He abandoned immigration reform, eventually coming out against his own bill. Most shocking, McCain, who had repeatedly denounced torture under all circumstances, voted in February against a ban on the very techniques of “enhanced interrogation” that he himself once endured in Vietnam—as long as the torturers were civilians employed by the C.I.A.