WASHINGTON (AP) — Here is a look of the key races in the 50 states:
ALABAMA — Republican Sen. Richard Shelby cruising to a fifth term in heavily Republican state. Republican Robert Bentley favored in gubernatorial race
ALASKA — Sen. Lisa Murkowski in unpredictable write-in campaign after losing GOP primary in tea party revolt. Republican Sean Parnell favored for governor
ARIZONA — Sen. John McCain coasting to fifth term after tough GOP primary. Gov. Jan Brewer also on track toward re-election. Four House Democrats in trouble.
ARKANSAS — Two-term Democratic Sen. Blanche Lincoln likely loser to Rep. John Boozman. GOP aims to win two open Democratic House seats.
CALIFORNIA — Former Gov. Jerry Brown leads Republican Meg Whitman in polls. Democratic Sen. Barbara Boxer in close race with Carly Fiorina.
COLORADO — Sen. Michael Bennet and tea party-backed Republican Ken Buck in close race. Denver Mayor John Hickenlooper favored for governor.
CONNECTICUT — Competitive governor's race between Democrat Dan Malloy and Republican Tom Foley. Attorney General Richard Blumenthal favored over GOP candidate Linda McMahon for Senate.
DELAWARE — GOP candidate Christine O'Donnell never got traction in Senate race versus Chris Coons. Rare pickup opportunity for House Democrats.
FLORIDA — Marco Rubio coasting to Senate win for GOP. Democrat Alex Sink and Republican Rick Scott in fierce governor's race. GOP targets four House seats.
GEORGIA — Republicans favored for governor (former Rep. Nathan Deal) and especially Senate (Johnny Isakson seeking another term).
HAWAII — Neil Abercrombie tries to regain governorship for Democrats. GOP Rep. Charles Djou tries to hang on. Eight-term Democratic Sen. Daniel Inouye poised to win another.
IDAHO — Republican C.L. "Butch" Otter headed for new term as governor. Republican Sen. Mike Crapo cruising to re-election in Senate. Democrat Walt Minnick wins tea party backing in re-election race
ILLINOIS — Republicans make play for governor, Senate seat and three House seats in Obama's home state. Real race is 2011 Chicago mayoral election.
INDIANA — Former GOP Sen. Dan Coats on his way back to Senate. Republicans poised to win one House Democratic-held House seat and challenge for two.
IOWA — Former Gov. Terry Branstad favored to defeat Democratic Gov. Chet Culver. Republican Sen. Charles Grassley coasting to new term.
KANSAS — Republican Sen. Sam Brownback awaiting election as governor. GOP Rep. Jerry Moran easing into Senate seat.
KENTUCKY — Tea party favorite Rand Paul builds modest lead in late polls in Senate race. Did Democrat Jack Conway's Aqua Buddha ad backfire?
LOUISIANA — GOP David Vitter on track to win new Senate term, says wife, family, God and voters forgive him in sex scandal. GOP Rep. Joseph Cao likely loser.
MAINE — Tea party favorite Paul LePage in competitive four-way governor's race.
MARYLAND — Gov. Martin O'Malley mild favorite for re-election after stiff challenge ex-Gov. Bob Ehrlich. Sen. Barbara Mikulski on track to win fifth term.
MASSACHUSETTS — Gov. Deval Patrick tries to fend off GOP challenger in Democratic-leaning state. Rep. Barney Frank pressed in tougher-than-expected campaign
MICHIGAN — Rick Snyder poised to return governor's office to GOP hands. Three Democratic House seats in play.
MINNESOTA — Former Democratic Sen. Mark Dayton and Republican Tom Emmer in competitive race for governor.
MISSISSIPPI — Republicans target Democratic Reps. Travis Childers and Gene Taylor in GOP-leaning state.
MISSOURI — GOP Rep. Roy Blunt coasting to Senate victory. Veteran Democratic Rep. Ike Skelton battling for new term.
MONTANA — GOP Rep. Dennis Rehberg coasting to new term in possible tune-up for 2012 Senate race.
NEBRASKA — GOP Gov. Dave Heineman en route to new term in heavily Republican state.
NEVADA — Senate Majority Leader Harry Reid in extremely close race with Republican Sharron Angle in state with 14.4 percent joblessness.
NEW HAMPSHIRE — Democratic Gov. John Lynch favored for fourth term. Republican Kelly Ayotte headed for the Senate in first run for federal office.
NEW JERSEY — GOP challenging Rep. John Adler in state where Democrats lost governor's office a year ago in early sign of voter anger.
NEW MEXICO— GOP prosecutor Susana Martinez slight favorite for governor in race against Diane Denish. GOP aims for two Democratic House seats.
NEW YORK — Democrat Andrew Cuomo comfortably ahead in polls for governor. Chuck Schumer and Kirsten Gillibrand poised to return to Senate from Democratic state.
NORTH CAROLINA — GOP Sen. Richard Burr cruising to re-election.
NORTH DAKOTA — Gov. John Hoeven gives GOP a solid shot at Senate pickup in seat held by retiring Democrat. Democratic Rep. Earl Pomeroy in trouble.
OHIO — Democratic Gov. Ted Strickland and former Rep. John Kasich in tight race; Rob Portman a likely Senate seat win for GOP.
OKLAHOMA — GOP Rep. Mary Fallin favored for governor while Tom Coburn coasts to re-election to Senate
OREGON — Democratic Sen. Ron Wyden poised to win re-election. Ex-Democratic Gov. John Kitzhaber and ex-pro basketballer Chris Dudley in close gubernatorial race.
PENNSYLVANIA — Competitive races for governor and Senate in classic swing state. Republicans eye House pickups.
RHODE ISLAND — Republican-turned-independent Lincoln Chafee tries for governorship his father once held. Democrat Frank Caprio criticizes Obama.
SOUTH CAROLINA — Tea party favorite Nikki Haley favored in gubernatorial race. GOP Sen. Jim DeMint coasting to likely win.
SOUTH DAKOTA — GOP Sen. John Thune cruising to re-election. Prelude to presidential race? Democratic Rep. Stephanie Herseth Sandlin struggling.
TENNESSEE — Bill Haslem favored for governor in Republican pick-up opportunity. Two Democratic retirements give House GOP big targets.
TEXAS — GOP Gov. Rick Perry favored over Bill White for new term.
UTAH — Republican Mike Lee coasting to Senate after tea party jettisoned GOP Sen. Bob Bennett last spring. GOP Gov. Gary Herbert likely winning new term.
VERMONT — Democratic Sen. Patrick Leahy poised to get six more years in seat he first won in 1974. Competitive race for governor.
VIRGINIA — Republicans take aim at three Democratic House freshmen. Obama campaigned late for one, Tom Perriello
WASHINGTON — Three-term Democratic Sen. Patty Murray has struggled in Democratic-leaning state against Republican Dino Rossi.
WEST VIRGINIA — Gov. Joe Manchin in close race with Republican John Raese to fill out the term of the late Sen. Robert Byrd.
WISCONSIN — Three-term Democratic Sen. Russell Feingold is the underdog to Republican challenger Ron Johnson. Governor's race competitive.
WYOMING — Governor's office looks headed back to Republicans with two-term Democrat retiring.
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