Today, it was Republican frontrunner's turn to answer mounting questions about one of his supporters, Rev. John Hagee, a San Antonio pastor with a worldwide broadcast ministry, reports CBS News senior political correspondent Jeff Greenfield.
Hagee has offered some highly provocative views on a variety of subjects.
For instance, he linked Hurricane Katrina to the gay rights movement: " … All of the city was punished because of the sin that happened there in that city."
He has also denounced the Roman Catholic Church as "the great whore of Babylon" and "a cult." He blames it for the Holocaust and predicts its imminent demise.
"This is the apostate church," Hagee said. " … this false religious system is going to be totally devoured by the anti-Christ."
In a statement, Catholics United said: "We hope Senator McCain will take the principled position of publicly and unequivocally distancing himself from Pastor Hagee's anti-Catholic comments."
And Bill Donahue of the Catholic League offered a tougher view: "I do want a clear-cut statement from McCain saying that he knows Catholics have been offended, when this man hagee calls my religon the great whore and a false cult system."
Today, Sen. McCain offered carefully measured words: "I don't have to agree with everyone who endorses my candidacy," he said. "They are supporting my candidacy. I am not endorsing some of their positions."
The question is whether Pastor Hagee's view on the Catholic Church constitutes "a position" or a view that the presumptive Republican nominee has to address head on.
This dust-up may also make it a lot tougher for Republicans to criticize Barack Obama for some of his more controversial supporters.