So says Politico, and they are probably right. Seven term congressman Mike Simpson from Idaho's 2nd district is about as GOP establiishment as you can get. A powerful member of the Appropriations Committee and long time friend of Speaker John Boehner, Simpson is the sort of congressman the Tea Party likes to hate.

He is being seriously challenged by Bryan Smith, an attorney who was handpicked by the Club for Growth to take on Simpson.

Smith is branding the eight-term Simpson as a dusty creature of Washington who has turned wobbly on the spending issues that are near and dear to the conservative cause. Simpson, meanwhile, is stressing that he is, in fact, a conservative while making the case that his experience and seniority are, in fact, plusses.

"Idaho's 2nd Congressional District is turning into a proxy war for the middle-right of the Republican Party and the right-right of the Republican Party," said Phil Hardy, an Idaho Republican operative and a political analyst in the state. "It's already happening."

The 2014 midterm elections will likely feature a long list of primaries in which House and Senate incumbents will encounter significant threats from insurgent challengers. If history is any guide, the vast majority of the sitting members - who typically benefit from a fundraising advantage and have nearly universal name ID within their districts - will prevail.

But there are indications that Smith's campaign is a more serious one. He's notched early endorsements from the Club and RedState founder Erick Erickson, which will help him expand his fundraising base beyond Idaho - where raising cash is hard. And Smith's backers call the district - where Mitt Romney captured an overwhelming 64 percent of the vote in 2012 - a perfect laboratory for waging a battle over which candidate hews more strictly to conservative ideology.

To survive, Simpson will be counting on the support of Washington's heavy hitters - and his friend Boehner in particular.

The speaker has already donated $5,000 to Simpson, and Boehner aides say more fundraising help is on the way. Boehner will head to Boise later this month to headline a fundraising event for the congressman.

Fotunately, no matter who wins this donnybrook, the GOP will almost certainly hang on to the seat. Romney won the district with 64% of the vote which means a Democrat would have a very hard time of it.

As a microcasm of what is happening nationally in the Republican party, the second district race should be a good barometer of how things might shake out as we get into the primary season next year.