Most are casting this as outing an incumbent during a time when there is much hatred of the way Congress works.

Three-term Sen. Bob Bennett became the first victim this year of a wave of voter anger toward Washington in a defeat that will likely send a jolt through incumbents everywhere.
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When it was announced that Bennett had been eliminated from the race, a huge ovation swept through the convention hall and there were hoots and shouts of “He’s gone! He’s gone!” Other delegates hugged and tea party members waved their yellow “Do Not Tread On Me” flags.
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Julian Zelizer, a professor at Princeton University, said that while Bennett’s defeat may have been an anomaly attributable to Utah’s unique convention system, any time a long-serving incumbent is beaten it sends shock waves.

“I think all incumbents are nervous right now. The polls are just showing that voters are unhappy with Democrats or Republicans,” he said.

Some, however, see Bennett, considered one of the Senate’s most conservative members, as not being conservative enough in that he voted for TARP and worked on healthcare with a Democrat.

Bennett, 76, initially faced seven Republican opponents who said he wasn’t conservative enough for ultraconservative Utah. Lee, 38, and Bridgewater, 49, campaigned largely by saying they’re better suited to rein in government spending than Bennett.

“I will fight every day as your U.S. senator for limited government, to end the cradle-to-grave entitlement mentality, for a balanced budget, to protect our flag, our borders and our national security and for bills that can be read before they receive a final vote in congress,” Lee said in his convention speech.

On the other hand, there’s this:

Utah’s quirky candidate selection process too often disenfranchises the rank and file. Electoral decisions are made by a few on behalf of the many thanks to a party caucus and convention system that concentrates the power in the hands of party elites.

For example, all it will take at Saturday’s Republican state convention is 2,100 votes — 60 percent of the delegates — for a U.S. Senate candidate to advance directly to the general election against a token Democrat. In other words, 2,100 people may speak for nearly 3 million. As a result, Utah voting rates are among the worst in the nation.

So, where does this leave other Republicans up for reelection this year? What about Democrats?