And then there were three.

Sen. Mary Landrieu (D-La.) has defeated state Treasurer John Kennedy (R), 52 percent to 46 percent, with 99 percent of precincts reporting, according to the Associated Press. And although the race has not been called, Sen. Saxby Chambliss (R-Ga.) is on track to outright defeat state Rep. Jim Martin (D) and avoid a Dec. 2 runoff.

With 95 percent of precincts reporting, Chambliss was leading 52 percent to 44 percent. Libertarian candidate Allen Buckley had 4 percent of the vote.

So with a 60-seat, filibuster-proof majority now out of reach for Senate Democrats, the final 2009 composition of the chamber now hinges on the outcomes in Oregon, Alaska and Minnesota.

With the polls closed in Oregon since 11 p.m. EST, state Speaker Jeff Merkley (D) was leading Sen. Gordon Smith (R) in Oregon with roughly 650,000 votes cast. According to the Oregon secretary of State, Merkley led Smith, 49 percent to 46 percent, while Constitution Party candidate Dave Brownlow took 5 percent of the vote.

In Alaska, polls have just closed and election officials have not begun to count the votes in the much-anticipated contest between recently convicted Sen. Ted Stevens (R) and Anchorage Mayor Mark Begich (D).

And in Minnesota, Sen. Norm Coleman (R) continues to run neck-and-neck with comedian Al Franken (D), with each at about 42 percent, according to the Minneapolis Star-Tribune. Former Sen. Dean Barkley (I) was taking a little more than 16 percent. But Franken could have an advantage, as not all of Hennepin County, which includes liberal-leaning Minneapolis, has reported results.

So far tonight, Democrats have knocked off incumbent Sens. Elizabeth Dole (R-N.C.) and John Sununu (R-N.H.) and won open-seat contests in Colorado, New Mexico and Virginia.

Republicans also successfully played defense in the Bluegrass State, where Minority Leader Mitch McConnell (R-Ky.) defeated wealthy businessman Bruce Lunsford (D), and in Maine, where Sen. Susan Collins (R) topped Rep. Tom Allen (D) rather handily.