Republicans are headed for big U.S. Senate gains in the Nov. 2 election but still face an uphill struggle to pick up the 10 Democratic seats they need for a majority.
The Republicans need to sweep nearly all of this year's competitive races to gain control of the 100-member Senate, where Democrats have a 59-41 edge. Thirty-seven Senate seats are up for election this year.
Republicans appear likely to hold all of their own seats, although the race in Kentucky has tightened, and have commanding poll leads in three Democratic-held states -- Arkansas, Indiana and North Dakota.
To pull off the majority, Republicans will need to string together wins in seven of eight tight races in California, Washington, Nevada, Wisconsin, Colorado, Pennsylvania, Illinois and West Virginia.
Here is a look at 12 of the top Senate races:
NEVADA - Senate Democratic leader Harry Reid, the biggest Republican target, is in a neck-and-neck re-election struggle with Republican Tea Party-favorite Sharron Angle in a state where the economy has nose-dived. Polls show Reid, the ultimate insider in an anti-Washington year, is viewed unfavorably by most voters -- but so is Angle. She told Reid to "man up" about his decisions on the economy. Reid, a former boxer, said his manhood had never been questioned before.
KENTUCKY - Republican Rand Paul, the son of Republican libertarian U.S. Representative Ron Paul and a darling of the conservative Tea Party movement, raced to a big lead over Democratic rival Jack Conway, but the contest to replace retiring Republican Jim Bunning has tightened. The two candidates meet in their final debate on Monday night. Paul refused to shake Conway's hand after their last debate, which featured a testy exchange about Conway's ad on a secret society he said Paul belonged to while a student at Baylor University.
CALIFORNIA - Vulnerable three-term Democratic Senator Barbara Boxer has solidified a small lead in polls over former Hewlett-Packard chief Carly Fiorina. President Barack Obama campaigned on Boxer's behalf last week in a state that is normally reliable for Democrats. The Senate Republican campaign committee said it would spend $3 million on advertising in the race's final days to help Fiorina.
WISCONSIN - Republican Ron Johnson has taken a solid lead by painting three-term Democratic Senator Russ Feingold as a big-spending liberal who backed the stimulus package and presided over a huge increase in the budget deficit. Feingold has launched a counter-attack accusing Johnson of supporting free-trade deals that cost the state jobs and of supporting the repeal of a healthcare overhaul that protects the sick.
ILLINOIS - Obama's former Senate seat, left vacant by the departure of appointee Roland Burris, is the focus of a tight and expensive battle between Republican Representative Mark Kirk and Democratic state Treasurer Alexi Giannoulias in a Democratic-leaning state. Republicans have painted Giannoulias as corrupt, while Democrats jumped on Kirk's inaccurate claims about his military record. A Chicago Tribune poll released on Monday gave Kirk a three-point edge.
WEST VIRGINIA - Popular Democratic Governor Joe Manchin was an early favorite to sweep into the vacated Senate seat of the late Democrat Robert Byrd, but Republican businessman John Raese has made it a tight race in a state where Obama is unpopular. Manchin pounced on a Sunday newspaper article showing Raese's company benefited from millions in state and federal contracts, calling it hypocritical for a man who has criticized government spending.
COLORADO - Democrat Michael Bennet was the Denver public school superintendent when he was appointed in January 2009 to the Senate to succeed Ken Salazar, who became Interior Secretary. Bennet is in a tight race with Tea Party favorite Ken Buck, who beat the Republican establishment candidate in a primary. A new Denver Post poll shows the race is a dead heat.
CONNECTICUT - Popular Democratic state attorney general Richard Blumenthal has faced an unexpectedly tougher race against big-spending former World Wresting Entertainment chief executive Linda McMahon. But he has solidified a double-digit lead in most polls in the Democratic-leaning state.
MISSOURI - Democratic hopes of capturing the Missouri seat of retiring Republican Christopher Bond are slipping away, with Republican Roy Blunt holding a solid lead over Robin Carnahan. Blunt, a seven-term congressman, has hammered Obama's agenda. Carnahan, whose family has a long history in state politics, has had a hard time winning over rural and small-town voters.
OHIO - Republican Rob Portman, a former congressman and Cabinet official under President George W. Bush, is another insider who has managed to avoid the wave of anti-Washington voter anger this year. He appears to have pulled away from underfunded Democrat Lee Fisher in a state where the stumbling economy and loss of jobs have been the dominant issue.
PENNSYLVANIA - Republican Pat Toomey has seen his once big lead on Democrat Joe Sestak disappear in a close and testy fight for the seat of incumbent Arlen Specter, who was knocked out by Sestak in the Democratic primary. Toomey, former head of the anti-tax group Club for Growth, has tried to tie Sestak to Obama's agenda and dismisses the tightening polls as a natural shift in the late stages of the campaign. A Sestak win would finish off Republican hopes of capturing a Senate majority.
WASHINGTON - Three-term Democratic Senator Patty Murray is in a close race with Republican challenger Dino Rossi after a heavy onslaught of television advertising from both sides. The state usually leans Democratic because of liberal Seattle and its suburbs, but Rossi accuses Murray of aiding the growth of the budget deficit and government spending. (Reporting by John Whitesides; Editing by Paul Simao)
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