Jeffords, a Republican as of this minute, will announce Thursday morning which party he plans to be a part of -- thus delivering control of the U.S. Senate to the Democrats. And as he does so, there are myriad reasons speculated as to why he is embarking on this journey.

President Bush began the push when he unveiled his plans for a $1.6 trillion tax cut. In a 50-50 Senate, Bush needed every vote, but Jeffords was reluctant to go along, thinking the cut too large. Unable to reach an agreement with the Bush White House after asking for increased funding for special education, Jeffords broke from the GOP fold, joining with a bunch of moderates from both parties to push a compromise $1.25 trillion tax cut. In the process, he aroused the wrath of the vengeful Texan, a man whose administrators have reportedly been flagging and often eliminating potential staffers if they supported Sen. John McCain, R-Ariz., during the 2000 GOP primaries.

So the retribution against Jeffords began. But Jeffords' staff says that there's more to Thursday's move than that.

"It's not about being snubbed by the White House," says Jeffords spokesman Erik Smulson, referring to a now-infamous dis: On April 23, President Bush's team didn't invite Jeffords, chairman of the Senate Health, Education, Labor and Pensions Committee, to the annual ceremony for the National Teacher of the Year award, which went to a Vermont social studies instructor.

"It's not about the Dairy Compact," Smulson goes on, referring to threats in the media made by unnamed GOP sources that Bush and his mercenaries might seek their revenge by having the GOP-controlled Senate kill off the Northeast Interstate Dairy Compact, which benefits Vermont dairy farmers.

"And it's not about any chairmanship," Smulson says. Jeffords, 67, will be term-limited out of his chairmanship of the committee next year. Democrats -- in exchange for Jeffords' possible support for now-Minority Leader Sen. Tom Daschle, D-S.D., to serve as majority leader -- are said to be willing to give him the chairmanship of the Environment and Public Works Committee, should they suddenly find themselves in charge of the Senate.

So, what is causing Jeffords to rethink a career as a Republican?

"It's more about his priorities," Smulson says.

Priorities aside, the White House's "Vengeance Is Mine, Sayeth the Bush" campaign -- a mystifying combination of charmlessness and cluelessness said to be orchestrated by senior presidential advisor Karl Rove and the White House's Hill lobbyist, Nick Calio -- seems to have worked its magic: Bush has now cut off his Jeffords to spite his face. Hooray for Bush! Bush wins!

Or does he? Suddenly, Bush's legislative agenda seems far less likely to become law, his judicial nominees far less likely to become federal judges, if -- as expected -- Jeffords becomes an independent and joins the Democratic Caucus. (Which is still a big if. "Sen. Jeffords has an independent streak in him as long as a Vermont mile," says a senior Democratic Senate aide, cautioning that no one knows exactly what Jeffords will do Thursday.)

Assuming he jumps ship, however, some of the credit for this can be attributed to the assistant Democratic leader, Sen. Harry Reid, D-Nev. Several weeks ago, Daschle and Reid got together to talk about opportunities possibly available to them. The Republican leadership didn't appear to be taking care of its members, the Democrats thought, and they seemed to be possibly alienating some of their more moderate members. Unlike the Republicans, there were no reports of internal strife over Sen. Max Baucus, D-Mont., who sided with the GOP on Bush's tax cut, or Sen. Zell Miller, D-Ga., who has sided with the GOP on most everything.

"It's a combination of Republicans needing Jeffords more than Jeffords needs Republicans," observes a former Senate GOP leadership aide. "That, and the fact that his care and feeding wasn't up to snuff."

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