John McCain of Arizona and Lincoln Chafee of Rhode Island have declared their intent to side with Democrats. Olympia Snowe is widely considered to be the third Republican who will vote "no."

There may be another Republican on the fence, Sen. Pat Roberts of Kansas:

Roberts expressed doubt about the "nuclear option," which would end a long-running Democratic threat to filibuster seven of President Bush's nominees for the federal bench by changing long-standing Senate rules.

"What goes around comes around," Roberts said in a recent interview, worried that the rule change could someday come back to haunt his party. Roberts said that while he opposes filibusters of nominees, he declined to say how he would vote. A former member of the House for 16 years where he spent most of the time in the minority, he said that it was "not in the best interests of either party or the Senate to take this step."

If you're not sure what's at stake, read this excellent op-ed in the Seattle Post-Intelligencer.