Will Mayor Bloomberg switch from Kirk to Giannoulias in the Illinois Senate race — fallout from the mosque?

No one, certainly not the backtracking President Obama, gave a more full-throated endorsement of building a mosque two blocks from Ground Zero in lower Manhattan than the mayor of New York.

In a small item in Tuesday’s New York Times, Bernie Becker reported that Mayor Michael Bloomberg, a Democrat-turned-Republican-turned-Independent, was supporting Mark Kirk in the race here for Obama’s old Senate seat.

On the same day, Alexi Giannoulias, who is depending on Obama/Biden — they’ve both been in Chicago to raise money for Treasurer Giannoulias — in a race that is polling even at the moment, announced at the State Fair in Springfield that he’s backing the mosque near Ground Zero.

Kirk is not, and his spokesman issued a statement that building the mosque there would cause relatives “undue pain” and that the mosque’s backers should build it on a “less controversial site.”

Will Bloomberg rethink his support of Kirk? No, according to his press secretary Stu Loeser, who e-mailed me: "The mayor was asked a similar question about Sen. Reid [who is opposed to building the mosque near Ground Zero] today in Philadelphia. Here's what he said: 'I happen to be a supporter of Harry Reid. I don't agree with him on everything, and I'm never going to agree with anybody on [everything]. Ed Koch once said if you agree with them 90 percent of the time, vote for them. If you agree with them 100 percent of the time, go see a psychiatrist.' The same applies to Rep. Kirk."

In the Pennsylvania Senate race, Bloomberg has just endorsed Democrat Joe Sestak against his conservative Republican opponent Pat Toomey.  Interestingly, while Kirk gave a direct  statement in opposition to the mosque—Sestak said that he backs the “constitutional right to religious freedom” but that he is “focused on Pennsylvania.”  In other words, he didn’t say.

This post was updated at 11:43 p.m.