The Tea Party has done a good job of purging one kind of Republican, what you might call the Total Squish – the Republican who just offers nothing on any issue to Republican voters. But to my mind, there are three other species of candidate that we need to do a better job of vetting and avoiding in the primaries, both national and statewide:

1) The Clueless Rich Guy: The wealthy or self-funded candidate with little or no political experience, no firm principles and, as a result, often an undue reliance on political consultants. Romney was not the only candidate of this species – Linda MacMahon also failed in Connecticut for a second consecutive cycle. Rookie politicians aren’t all bad (see Ron Johnson, for example), but as a group they make a lot of mistakes, and wealthy ones are often poor messengers for our ideas.

2) The Pulled Hand Grenade So-Con: Social conservatives are a crucial part of the Republican coalition, and I’d be the last person to want to run them out of the party. But it takes a high level of self-delusion to avoid the fact that candidates like Todd Akin simply have no clue how bad their pronouncements sound to voters outside their corner of the base – and in Akin’s case, he won the nomination over two equally plausible alternatives who would have beaten Claire McCaskill. Richard Mourdock, unlike Akin, had won statewide races and didn’t have a real record of saying things that would set off alarm bells – plus he won his primary against an incumbent far past his sell-by date – but one poor answer in a debate finished him. Social conservatives as a group need to accept the fact that communication and tone matter; people will respect your issue stances, but not if you seem to them like a frightening extremist. We need to find better ways of identifying people who just won’t fly with the general electorate before it’s too late.

3) The Retread: Two of the failed Senate candidates (Tommy Thompson and George Allen) were excellent statewide candidates…in the 90s. But much like Newt Gingrich and Rick Santorum, they found it hard to adjust to the current political environment. Voters looking for change are a lot less likely to pull the lever for a guy who has been out of the fight that long.