One problem is that Tea Party extremism is so far out and obscure that it doesn't immediately register as extremism. They want to repeal the 17th Amendment! That sounds odd, but most of us don't know off-hand what the 17th Amendment is. And even after being reminded that it's the one that has to do with direct election of senators, it's still not clear why they want to repeal it, other than the fact that it was passed during the Progressive Era. It takes a lot of explaining, and I still don't quite get it, plus it seems so unlikely to happen that I can't get too worked up about it. (There's also the fact that living in Washington, D.C., without senators, I don't have a vote to lose.)
More importantly, the Tea Party movement's embrace of eccentric constitutionalism and rhetorical libertarianism has had the effect of moving social issues to the background. Most of the Tea Party activists, and all of their candidates, hold the same cluster of not-very-libertarian views on social and cultural issues as their far-right predecessors, usually several degrees more extreme. (Angle, for example, has said that a young teenager who becomes pregnant as a result of rape by her father should "make a lemon situation into lemonade.") But those views are obscured behind a confusing screen of constitutional and economic nonsense.
These social views are the positions that voters, especially the younger voters and suburbanites who turned decisively against Republicans in 2006 and 2008 and who are now wavering, understand. They don't need to find a copy of the Constitution to decipher the extremism. Remember that there were two issues during the Bush years that dramatically illustrated to voters the extremism of the Republican far right at that time. The first was the case of Terry Schiavo, in which congressional leaders sought to intervene in a family's private medical tragedy. The Schiavo intervention, opposed by 70 percent of the public, derailed Congress and the Bush presidency in the early months of 2005, contributing to the subsequent defeat of Social Security privatization.
He concludes: "In an ideal world, it would be as easy to show just that the economic views of the new Republican stars are as extreme and unhinged as their social views. But it's probably too late to start that now."
In other words: Governance is hard and complicated! Rather than make our case to the voters based on the substance of our views and actions, let's do the culture war thing instead so we can signal to them that the other guys are out-of-touch with our "values" in ways that don't have very much to do with governance!
Which, basically, is the left-wing version of this:
I'm not naive: Value-signaling always will be part of democratic politics. But the Schiavo Affair turned off voters because it signaled to them that Republicans had embraced culture-war issues to the exclusion of effective governance. Obsessing about Christine O'Donnell's views of masturbation might do the same thing to Democrats.