Philip Klein delivers some unconvincing Tea Party spin on Lugar’s loss:

Any elected Republican that doesn’t pursue a small government agenda once in office risks suffering the same fate as Lugar. Had Lugar hung on, then a lot of people would have dismissed the Tea Party as a passing fad from 2010. But now it’s clear that the movement has been underestimated once again. Tea Partiers have a lot more staying power than skeptics expected.

This is a major overreaction, but it isn’t as implausible as Klein’s other idea that Romney “will be forced to govern as a limited government conservative if elected.” For that to happen, Romney would have to believe that he would face a serious primary challenge at the next election, and there isn’t much reason for him to believe that. There is always a danger of reading too much into any one primary result, and Klein is definitely reading too much into Lugar’s defeat.

Lugar had a number of political liabilities that were unique and don’t apply to most Republican incumbents. Lugar also had a challenger with a record of being elected to statewide office, which made it easier for dissatisfied Republicans to throw their support to Mourdock without having to worry that they were nominating an unelectable candidate. For the most part, the votes that provoked the conservative backlash against him had little or nothing to do with the size or role of government. If Mourdock’s victory sends any kind of message about policy, it is that Republican voters object to bailouts and anything they perceive as immigration amnesty, and they don’t like their politicians to be too close to Obama, which everyone already knew. The larger message is that elected representatives shouldn’t lose touch with their constituents, and they shouldn’t become so accustomed to their position that they stay in Washington forever. That isn’t some shocking new revelation. It’s political common sense, which Lugar neglected at his peril.