With all the usual caveats about early polls in play, the generally reliably trending USA TODAY/Gallup Poll has seen a rather abrupt turn in the battleground states over the past month among one demographic. Women.

President Obama has opened the first significant lead of the 2012 campaign in the nation’s dozen top battleground states, a USA TODAY/Gallup Poll finds, boosted by a huge shift of women to his side.

In the fifth Swing States survey taken since last fall, Obama leads Republican front-runner Mitt Romney 51%-42% among registered voters just a month after the president had trailed him by two percentage points.

The biggest change came among women under 50. In mid-February, just under half of those voters supported Obama. Now more than six in 10 do while Romney’s support among them has dropped by 14 points, to 30%. The president leads him 2-1 in this group.

We’re still waiting for the D/R/I, so there’s more than a little chance that the hard number is much closer than the top line here. But, as always, we tend to watch the trend lines more the “concrete” figures. This is one poll which has tracked fairly closely in past months with other surveys which showed Obama’s support wavering in a number of areas, frequently cited by conservative pundits. In fact, at the close of February, Obama was losing this demographic (women) by a slight margin and struggling against Romney. Why the change?

Republicans’ traditional strength among men “won’t be good enough if we’re losing women by nine points or 10 points,” says Sara Taylor Fagen, a Republican strategist and former political adviser to President George W. Bush. “The focus on contraception has not been a good one for us … and Republicans have unfairly taken on water on this issue.”

This was always going to be a dicey issue, but the media has really brought it to the forefront, though still not as much as jobs and the economy. Demographic prognostication is always tricky at best, particularly when you’re trying to measure the impact of minority groups. But when it comes to the “he said she says” vote, you can’t dodge very many bullets. Romney will have to do much better than this with women across all demographic lines in the swing states. So, assuming he winds up being the nominee, some damage control may be in order on this front.