The presidential race plays a crucial, tidal role in so-called down-ballot races, exerting an inexorable pull that’s difficult to resist. This year, with Trump trailing in most national polls, it’s an extremely dangerous environment for certain Republican senators. With Democrats hoping to pick up at least five seats, which would put them back in the majority, they’re targeting Ayotte, Illinois Senator Mark Kirk, Wisconsin Senator Ron Johnson, and several others in blue or purple states.

All of the endangered GOP incumbents are adopting versions of the same strategy: Localize and personalize. There will be no more statewide ads on Obamacare. Instead, voters will hear about how their representatives brought home the bacon, even if they had to buck party leaders, or even party orthodoxy, to do it.

The challenge is to surf Trump’s outsider wave—and not alienate his voters—without being trapped in some of his noxious positions and personal unpopularity. Candidates “should be, and I’m sure they will be, highlighting how they’re different from Washington as usual,” said Los-Angeles based GOP ad maker Fred Davis.