CBS News poll: Democrats lead in Michigan, Pennsylvania, Wisconsin Senate races

Though Democrats face a formidable U.S. Senate map in 2024, they're currently ahead in three key races.

In CBS News' first poll of the race for Michigan's open Senate seat, Democratic Rep. Elissa Slotkin is leading former GOP Rep. Mike Rogers by seven points. Meanwhile, Sens. Bob Casey of Pennsylvania and Tammy Baldwin of Wisconsin are ahead in their reelection bids by seven points and eight points, respectively.

The races in Pennsylvania and Wisconsin look similar to our initial read in the spring , with the main difference being that there are fewer undecided voters now. In both states, the percentage who are not sure of their Senate vote has decreased by four points, with Democratic and Republican candidates in each race gaining more or less equally.

While the presidential race currently looks very close in all three states, the Democratic Senate candidates are benefiting from just enough ticket splitting to edge ahead. Casey and Baldwin currently lead among independents, who are more or less evenly divided between Democratic nominee Kamala Harris and GOP nominee Donald Trump in the presidential race. And while Republican voters are backing their party nominees in large numbers in all three states, GOP Senate candidates are still running behind Trump among them. That both explains their current deficits and also suggests there's room to grow.

These estimates are snapshots of the race, not predictions. With eight weeks to go until Election Day, there is still time for things to shift. One good reason we might expect the races to tighten is that undecided voters profile as Republican-leaning. They are backing Trump for president in fairly large numbers, and their past votes and partisanship suggest they are closer to the GOP. If these voters ended up choosing the same party for Senate as they do for president, the Democrats' leads in all three races would shrink to within the margin of error.

These CBS News/YouGov surveys were conducted between September 3-6, 2024. They are based on representative samples of 1,086 registered voters in Michigan, 1,085 in Pennsylvania, and 958 in Wisconsin. Margins of error for registered voters: Michigan +/- 3.7 points, Pennsylvania +/- 3.5 points, and Wisconsin +/- 4.0 points.

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