Ben Smith had an interesting item this morning about how Obama is up with a radio ad targeting McCain on abortion. To those who recall Republicans wrapping abortion around the necks of previous Democratic nominees, this may seem like a counterintuitive move. But it actually makes a lot of sense:

1.) The majority abortion position in the United States, according to most polls, is in favor of restrictions but against outlawing the procedure. When you can cast your opponent as an extremist on the issue, it tends to be a winner. I haven't heard the ad, but between McCain and Palin, both of whom have very conservative abortion records, there should be opportunities to do that.

2.) The issue especially resonates with the women--particularly moderate Republican women--Obama is counting on to offset losses among blue-collar Democrats. There's historical precedent for this: When Doug Wilder ran for governor in 1989, his campaign aggressively flogged the abortion issue as a way to pick up moderate white women and compensate for similar defections among downscale whites. (Wilder's campaign manager, Paul Goldman, once told me their poll numbers dipped any time they took their abortion ads off the air.) Wilder, of course, became the first African American elected governor of a U.S. state.

3.) Relatedly, this reminds women tempted by the Palin pick that voting Republican sets back a cause they care about deeply.

Update: Ben followed up with a piece about the ad. Here's the gist:

“Let me tell you: If Roe vs. Wade is overturned, the lives and health of women will be put at risk. That's why this election is so important,” says the nurse-practitioner who narrates Obama’s ad. “John McCain's out of touch with women today. McCain wants to take away our right to choose. That's what women need to understand. That's how high the stakes are.”

An announcer then claims that “As president, John McCain will make abortion illegal,” before playing an exchange on "Meet the Press" in which McCain told Tim Russert that he favors “a constitutional amendment to ban all abortions.”

“We can't let John McCain take away our right to choose. We can't let him take us back,” says the ad.

--Noam Scheiber