That's exactly what they did with Bill Clinton back in the 92 campaign. It was already old news once the campaign got into swing.
Even Trump got his stuff out of the way, relatively early.
That’s the way to run a campaign these days. Get ANY and ALL bad/controversial stuff out early so it’s really old by election time. Of course, Trump had been a very public figure as a private citizen, known as a playboy, so there wasn’t much they could do except that absurd dossier.