I think Trump is being very, very clever.
He accuses Hillary of playing the "woman card." And then audaciously claims that "if she were a man she wouldn't get 5% of the vote." (That latter statement is true: were she a man she'd be an establishment figure like Jeb Bush or Martin O'Malley.)
Hillary falls for the trap: she prints up "woman cards" to distribute to her donors, and comes up with PBS-like gifts, such as handbags that proclaim "a woman's place is in the White House."
So people who really care about having a woman for president are probably 20-25% of the electorate. And they're already gonna vote for Hillary, regardless of what Trump says. So he's giving her that slice of the vote.
But what he's also doing is tagging her as a single-issue candidate. The ONLY reason to vote for Hillary, Trump will claim, is because she's a woman. He's cornering her so indelibly as the 'woman candidate' that she'll never get another word in edgewise. If you care about anything else then you should vote for Trump. And as I said, she's falling for it hook, line and sinker.
So expect Trump to keep making attention-getting remarks about Hillary as a woman. That'll win him every news cycle. And then: she voted for the Iraq war; she voted for NAFTA; she supported the TPP; she's against the wall; she couldn't answer the phone at 3am when Benghazi called; she lacks the energy and stamina to be president; she's old and sick. Maybe Corrupt Hillary really is a woman, but she can't Make America Great Again.
If Hillary can't escape that trap then Donald wins hands down.