Alaska Sen. Lisa Murkowski fought to save her job Wednesday, locked in a stunningly tight Republican primary race against a political novice backed by Sarah Palin and tea party activists. The outlook was far brighter for another incumbent, Sen. John McCain, who won handily in Arizona.

With 98 percent of election day precincts counted, Murkowski trailed Joe Miller by 1,960 votes out of more than 91,000 counted. The race was too close to call, with as many as 16,000 absentee votes and an undetermined number of provisional or questioned ballots, remaining to be counted starting on Aug. 31.

Murkowski would be the seventh incumbent — and fourth Republican — to lose in a year in which the tea party has scored huge victories in GOP Senate primaries and voters have shown a willingness to punish Republicans and a handful of Democrats with ties to Washington and party leadership. Miller is a Gulf War veteran and self-described “constitutional conservative.’’

It also was an outsider’s night in Florida’s GOP primary for governor, with big-spending upstart Rick Scott toppling veteran insider Bill McCollum, the state’s attorney general who had the support of national party chiefs.

Five states — Arizona, Vermont and Oklahoma also voted — held nominating contests Tuesday, 10 weeks before the general election. The races highlighted dominant themes of this volatile election year, including anti-establishment anger and tea party challenges from the right.

Elsewhere, the establishment prevailed.

McCain easily cinched his party’s renomination — and likely re-election this fall — by dispatching former Rep. J.D. Hayworth, who had tea party support. The 2008 GOP presidential nominee spent more than $20 million on the primary. Rep. Kendrick Meek cruised to the Democratic Senate nod in Florida against a wealthy political newcomer. And a slew of Republican and Democratic members of Congress withstood primary challenges.