Can Mark Sanford succeed in his improbable comeback? According to the final poll of South Carolina’s 1st Congressional District ahead of the special election tomorrow, he’s going to make it close.  PPP puts Sanford ahead for the first time by the thinnest of margins, and reports that momentum has shifted his way in the heavily Republican district:

PPP’s final poll of the special election in South Carolina’s 1st Congressional District finds a race that’s too close to call, with Republican Mark Sanford leading Democrat Elizabeth Colbert Busch 47-46. The 1 point lead for Sanford represents a 10 point reversal from PPP’s poll of the race two weeks ago, when Colbert Busch led by 9 points at 50-41.

Sanford has gotten back into the race by nationalizing it and painting Colbert Busch as a liberal. A plurality of voters in the district- 47%- say they think Colbert Busch is a liberal compared to 43% who characterize her as ideologically ‘about right.’ Colbert Busch’s favorability rating has dropped a net 19 points compared to 2 weeks ago, from +25 then at 56/31 to +6 now at 50/44.

Sanford has spent most of his time running against Nancy Pelosi, and PPP says that strategy worked.  By tying Colbert Busch to Pelosi, he’s undermined her claim to be a centrist, although the Democrat has managed to do some of that work herself.  Despite running against ObamaCare, she demurred when it came to actually doing something about it:

The Sanford campaign has consistently argued that Colbert Busch will be a reliable vote for Nancy Pelosi, and after Sunday’s conference, a few national reporters peppered her with questions about potential disagreements she could have with House Democratic leadership.

“You heard congressman Clyburn himself say, sometimes you agree and sometimes you don’t, but let’s get to May 7th and let’s get elected, and then we’ll sit down and we’ll all talk to each other, we’ll collaborate with each other, we’ll work with each other,” she told the group.

When BuzzFeed’s Kate Nocera asked her how she would vote on an impending House bill to repeal the Affordable Care Act, Colbert Busch described the president’s signature piece of  legislation as “so problematic.”

“Will you vote to repeal it?” asked Yahoo!’s Chris Moody

“I have to see the bill,” she responded, adding that she didn’t want to comment on hypothetical legislation.

“It will say, ‘Repealed,’” responded Moody.

“Let’s see it,” she responded. “Let’s get elected on May 7th, and then we’ll go from there. And then when they bring it to the desk, we’ll go from there.”

If the Sanford campaign is on its toes, it will have that as a radio and/or TV spot sometime today.  This should have Democrats worried about the impact that Pelosi will have on other swing districts, too.  They embraced her instead of jettisoning her after the 2010 midterm debacle.  Another may be coming.

That may also be in part why Republicans have decided to return to the voting booth over the last few weeks:

The other key development in this race over the last two weeks is that Republicans are returning to the electorate. On our last poll, conducted right after the trespassing charges against Sanford became public, we found that the likely electorate had voted for Mitt Romney by only 5 points in a district that he actually won by 18. That suggested many Republican voters were depressed and planning to stay home. On our final poll we find an electorate that’s Romney +13- that’s still more Democratic than the turnout from last fall, but it’s a lot better for Sanford than it was a couple weeks ago.

It may be even more than that.  After Sanford’s affair and trespassing charge, one might have expected women to flee from his banner.  He’s not winning among women, but he’s only trailing among women by eight points, 43/51 — a very surprising result against a female candidate. Sanford leads among men by 11 points, 51/40, but the key here is women.  Democrats had to expect better than a +8 by running Colbert Busch in the district, but she’s only a +10 in favorability with women at 52/42.  Sanford’s at a -16 at 40/56, but it’s not damaging him nearly as much as anyone would have predicted.

Now it’s all about turnout and GOTV efforts.  Sanford is an old hand at those tasks, but we’ll see whether he can outdo the Democrats in this very Republican district in a high-profile special election. Figure on a late night tomorrow before we know anything.