Republicans will edge close toward control of the Senate Tuesday but are unlikely to be able to seal the deal.
While the GOP is widely favored to win back the House, it faces a narrower path to victory across Capitol Hill. Political prognosticator Charlie Cook calls the chances of Republicans picking up the 10 seats they need to wrest the upper chamber from Democratic control "non-existent."
Mississippi Gov. Haley Barbour, chairman of the Republican Governor's Association, told CBS' "The Early Show," that the House will likely flip, but "it's harder in the Senate. It's more of a stretch."
The current partisan breakdown in the upper chamber is 57 Democrats, 41Republicans and two independents who caucus with the majority.
Incumbents in more than a third of the Senate seats up Tuesday are considered safe.
At least two open Democratic seats -- North Dakota, where Gov. John Hoeven is running virtually unopposed, and Indiana, where former GOP senator Dan Coats holds a comfortable lead -- have all but been transferred to the Republican column. Republican seats in Missouri, Ohio and New Hampshire are likely to stay red.
Here, from east to west as polling places close, is a rundown of races to watch:
and West Virginia
will offer clues to which party will control the Senate when the night is over and whether the much-heralded Republican wave crested too soon
, Democratic Attorney General Richard Blumenthal has rebounded from damaging revelations about his puffed-up Vietnam War service to take a lead over Republican Linda McMahon, the former wrestling mogul who's taken some body blows over her treatment of pro wrestlers.
Gov. Joe Manchin was the heir apparent when Democratic legend Robert Byrd died in June. But an electorate that rejected Barack Obama in 2008 has been receptive to Republican businessman John Raese's message that Manchin will be a rubber stamp while Raese is the "Nobama" candidate. The special election had been rated a toss-up but has moved in Manchin's direction in the final days.
Congressman Joe Sestak bucked his party's establishment to take on five-term incumbent and former Republican Sen. Arlen Specter in the Pennsylvania
Democratic primary. Sestak won but now is in a bruising battle with GOP nominee Pat Toomey for a seat that normally would shade blue but this year appears to be turning red.
could have bragging rights to the first senator from the tea party
if Republican Marco Rubio maintains his growing double-digit lead. Gov. Charlie Crist, who entered the race as an independent after losing the GOP primary, has been unable to catch up in the three-way contest. Democratic Rep. Kendrick Meek has denied reports that former President Bill Clinton asked him to drop his struggling third-place campaign and throw his support to Crist. Meek refused and it was unclear whether a statement late last week by a Crist adviser that the independent would caucus with Senate Democrats if elected would persuade enough anti-tea party Democrats to hold their nose and vote for the governor.
Another tea party candidate, Rand Paul, was having a tougher time in Kentucky
until his Democratic opponent Jack Conway possibly overstepped the bounds
with a campaign ad attacking the Republican for his "Aqua Buddha" college prank. The spot appears to have backfired and allowed Paul to open up a wide lead in polls.
Rounding out the eastern time zone is Delaware
, home to one of the most entertaining Senate races this year. Once a slam-dunk for Republicans eager to swipe Vice President Biden's old seat with moderate Rep. Mike Castle, the presumed nominee, the race was upended when perennial candidate Christine O'Donnell, a tea party favorite, pulled an upset in the primary. Democrat Chris Coons, the relatively colorless New Castle county executive, is now the heavy favorite in a bewitching
campaign full of speech sometimes free
of facts. But O'Donnell insists the race is closer than pundits predict.
Republicans still have a chance for another trophy in Illinois,
where Republican Rep. Mark Kirk hopes to snag President Obama's old Senate seat. He'll have to defeat Democratic state treasurer Alexi Giannoulias, who has been battered by sordid headlines about his family's troubled bank. The two have traded razor-thin leads all fall, but Kirk appeared to be pulling ahead in the final stretch.
Perhaps the biggest fish that could be washed away by a Republican wave is Wisconsin
Sen. Russ Feingold. The three-term liberal populist, whose signature campaign-finance-reform law
was recently gutted by the Supreme Court in a decision that opened the floodgates for corporate spending in this election, is behind tea party candidate Ron Johnson in every recent poll.
Prospects also look bleak for conservative Democrat Blanche Lincoln in Arkansas
. She survived a strong primary challenge from the left only to hobble into the general election against GOP Congressman John Boozman. Political pundit Larry Sabato calls her "Dead Woman Walking."
Nothing much to see in the mountain time zone other than Colorado
, where the race is tightening between appointed Democratic incumbent Michael Bennet and Republican tea party favorite Ken Buck. Recent polls had them statistically tied.
Moving west into Nevada
brings into view the night's marquee race between Senate Majority Leader Harry Reid and tea party challenger Sharron Angle. Despite -- or more likely because of -- his powerful perch in Washington, Reid has been unable to shake
Angle in spite of numerous controversies
in her campaign. Now, though, one respected Las Vegas odds maker
gives Reid a narrow lead based on early voting.
, Democratic Sen.Barbara Boxer appears to have shaken off former Hewlett Packard CEO Carly Fiorina and is favored to win in the blue-leaning state. Polls show independents, who elsewhere have gravitated toward the Republican column, consider Fiorina, who has sought tea party support, too conservative for California.
To the north in Washington
state, Democratic incumbent Patty Murray holds a thin lead over Republican Dino Rossi, who is trying to avoid becoming a three-time loser after two failed runs for governor. Both President Obama and the first lady have been out to campaign for Murray. That might be enough to help Murray eke out a small but winning margin.
Finally, there is Alaska
, where incumbent Lisa Murkowski could become only the second senator, after Strom Thurmond in 1954, to be elected in a write-in campaign. Tea party insurgent Joe Miller, who thumped Murkowski in the Republican primary, had been favored in the three-way race with Democrat Scott McAdams, the mayor of Sitka. But ethics problems
and missteps such as lauding East Germany's security apparatus
and handcuffing a reporter
have sent Miller's numbers south and buoyed Democratic hopes of an unlikely pickup
in what promises to be a fitting nightcap to a wild Senate season.
More Information: News and Predictions on All Senate Races