Maine’s Second Congressional District, which encompasses most of state north of Portland and Augusta, offers one of the more competitive House races this cycle. Incumbent Republican Bruce Poliquin beat Democrat Emily Cain to win this seat in 2014, and she’s back for a rematch. (Polquin won by a pretty solid margin, 47 percent to 41 percent.)

The district has preferred the Democratic nominee for the past six presidential elections, but the National Republican Congressional Committee is hitting the airwaves with an ad tying Cain to Hillary Clinton:

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At first glance, tying Cain to Clinton, the candidate who is more likely to win, might seem unwise. But a June poll put Trump narrowly ahead in the Second District, and that same poll found 64 percent of likely voters have an unfavorable view of Hillary Clinton. (Nationally, Clinton’s favorable rating is now no better than Trump’s and may actually be getting worse than him.)