When a politicians betrays his voters, whom else won't he betray?

Geoff Kelly reports:

In the buildup to New York State’s legalization of same-sex marriage, New York City Mayor Michael Bloomberg pledged his help—that is to say, his money—to any Republican state senators who would cross their leadership and vote yes.

... In [Sen. Mark] Grisanti’s case, the timing of [Mayor Bloomberg's] fundraiser adds an intriguing wrinkle: By the next day, October 14, Grisanti must decide if he’s sticking with the Republican Party or returning to the Democrats, from whence he came. There has been much speculation that he might do so in order to retain his seat: The 60th District is heavily Democratic and likely to remain so even after redistricting; Grisanti’s vote on same-sex marriage caused much consternation among conservatives...

If Grisanti makes the switch, control of the Senate would be split, 31 senators on each side of the aisle, with four independent Democrats caucusing separately—a breakoff faction that Grisanti could join.

...In the meantime, imagine how it will frustrate some Republicans around here if Grisanti rakes in a couple hundred thousand dollars at one fundraiser, then defects to the Democrats the next day—taking with him all that campaign money, some of which might have filtered to other local GOP candidates and their operatives.