The road to a Republican majority in the Senate could hinge on what happens in Alaska, where Sen. Mark Begich is fighting for his political life and, like other vulnerable Democrats, is trying to distance himself from President Obama and some of Mr. Obama’s unpopular policies.
Kyle Kondik of the University of Virginia’s Center for Politics said Alaska could be ground zero.
“Only a relative handful of voters will decide whether Sen. Mark Begich, Democrat, keeps his seat in Alaska, but they may end up deciding which party controls the Senate,” Mr. Kondik said. “Even though the West is dominated by the two American megastates, California and Texas, sparsely populated Alaska is holding the West’s most important congressional contest this year.”
Mr. Begich will face off against the winner of the Aug. 19 Republican primary race among lawyer Joe Miller, who ran in 2010; former Alaska National Resources Commissioner Dan Sullivan; Lt. Gov. Mead Treadwell; and Air Force veteran John Jaramillo.
The race also will have a third-party candidates, which some political observers say could tip the scales of the election.
Republicans need to pick up a net of six seats to win control of the Senate. They have expanded their map of possible pickups in Colorado, where Republican Rep. Cory Gardner is challenging Democratic Sen. Mark Udall.
Polls show Mr. Gardner and Mr. Udall are running neck and neck.
In House races, Democrats are on the defensive in a number of Western states, including Arizona, where the races in the 1st and 2nd congressional districts are considered tossups.
The incumbents in those races, Reps. Ann Kirkpatrick and Ron Barber, are two of the nine Democrats who hold seats in districts that Republican candidate Mitt Romney carried in the 2012 presidential election.
Mr. Kondik, meanwhile, said the race in Colorado’s 6th Congressional District “could be the hottest, most expensive House race in the whole country.”
In California, Carl DeMaio, a former San Diego City Council member, is trying to unseat Rep. Scott H. Peters, a Democrat, to become the first openly gay Republican elected to Congress.
Prognosticators expect Republicans to maintain control of the House and possibly grow their more than 30-seat margin. Of the 17 races considered tossups by RealClearPolitics, Democrats are defending 14 of them.
The following are races to watch in the West, according to The Rothenberg Political Report, the University of Virginia Center for Politics and TheGreenPapers.com.