Horse race polls, favorability ratings, those will all fluctuate many times between now and next November. But if Clinton can’t find a way to engage unmarried women, millennials and minority groups — it’s going to be over for her.

That’s why this Democratic poll released on Monday, taken by Greenberg Quinlan Rosner Research on behalf of several liberal groups, should be seen as so troubling for Democrats.

Though, on the surface, it points to a real opportunity for Democrats to retake control of the Senate, beneath the surface it shows a lack of interest among millennials, unmarried women and minorities relative to the interest being shown from more traditional Republican voting blocs.

Specifically, 71 percent of seniors said they were “extremely interested” in the presidential election; 70 percent of conservatives and 70 percent of Republicans said the same. In contrast, just 65 percent of Democrats, 63 percent of minorities, 60 percent of unmarried women and 42 percent of millenials said they were “extremely interested.”