There’s a reason why Democrats spent over $1.5 million trying to help Akin win his three-way primary. He was the most conservative candidate in the field — and the most unpredictable one. He shook up his campaign staff late last year. He recently released a head-scratching and jumbled campaign ad. And Democrats have already launched a microsite highlighting his controversial statements that won’t play well with moderates. (“America has got the equivalent of the stage III cancer of socialism because the federal government is tampering in all kinds of stuff it has no business tampering in,” Akin once said.)

The latest example is a new radio ad paid for by the Democratic Senatorial Campaign Committee that attacks Rep. Todd Akin (R), but does so slyly, in a manner that appears to be designed to endear him to conservative voters.

“Todd Akin calls himself the true conservative, but is he too conservative?” asks the narrator of the ad, which is approved by McCaskill’s campaign and paid for by the DSCC. The narrator goes on to note the negative posture Akin has taken toward President Obama, before concluding, “it’s no surprise Todd has been endorsed by the most conservative leaders in our country – Michele Bachmann and Mike Huckabee.”

Bachmann and Huckabee are popular among conservative voters and are from states in the same geographic region as Missouri. If anything, many undecided conservative primary voters who hear their names in the radio ad would be tempted to give him a closer look.

According to a Republican strategist tracking ad buys in the race, McCaskill’s campaign and [the Democratic-aligned] Majority PAC have each spent about $850,000 on ads during the last two and a half weeks – more than Akin has spent on commercials during the entire campaign. So if Akin wins the primary, he might be able to credit some very unlikely allies.

Sen. Claire McCaskill, D-Mo., appeared on MSNBC’s “Morning Joe” Monday, where she declined to weigh in on whether GOP Missouri Senate nominee Todd Akin should drop out in the wake of his controversial comments that “legitimate” rape can’t lead to pregnancy.

“It’s not my place to decide,” said McCaskill. “I really think that for the national party to try to come in here and dictate to the Republican primary voters that they’re going to invalidate their decision, that would be pretty radical. I think there could be a backlash for the Republicans if they did that.”