Democrats in Senate races show lead in Michigan, Wisconsin and Pennsylvania as presidential race remains tight

Vice President Kamala Harris and former President Donald Trump face a tight contest in November. But as they fight to gain support of battleground states across the country, Democrats are seemingly ahead in three key races as they try to continue their control of the Senate.

A new CBS News poll shows Democrats with a lead in Senate races in Michigan, Pennsylvania and Wisconsin. The poll was conducted between Sept. 3-6 and answers were based on a sample of over 1,000 registered voters in those three states. The margins of errors are plus or minus 3.7% in Michigan, 3.5% in Pennsylvania and 4% in Wisconsin.

In Michigan, Democratic Rep. Elissa Slotkin is a former GOP Rep. Mike rogers by seven points, at 48% to 41%.

Sen. Bob Casey of Pennsylvania also has a comfortable lead against his opponent, former Secretary of the Treasury for International Affairs, Dave McCormick. That race currently stands 48% to 41%, according to the CBS News poll.

The new study shows Wisconsin to have the biggest gap, with Sen. Tammy Baldwin led Eric Hovde by eight points, at 51% to 43%.

The figures in Pennsylvania and Wisconsin look similar to initial polls in the spring by CBS News, 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 Democrats and Republican candidates in each race gaining more or less equally.

The results come as the presidential race in these states, particularly Pennsylvania, remain increasingly tight.

For instance, according to a national poll by The New York Times/Siena College, Trump and Harris enter the homestretch of the campaign in a tight race, with the Vice President in particular facing a sizable share of voters who still say they need to know more about her.

In the presidential race, Harris leads in all three of these battleground states, though her lead is nowhere near comfortable.

According to the New York Times poll, In Wisconsin, the Vice President polls at 50% compared to Trump's 47%. In Michigan, she stands at 49% with Trump gathering 47%. In Pennsylvania, one of the key states needed to win the White House, Harris polls at 49% and Trump at 48%, representing a statistical tie.

But while this is the case for the presidential race, Democratic Senate candidates could still benefit from just enough ticket splitting to edge ahead, CBS News suggests.

Casey and Baldwin currently lead among independents, who are more or less evenly divided between Harris and Trump. 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 the current deficits and also suggests there's room to grow, the study suggests.

As both parties try to gather independent support, one of their biggest opportunities to do so lies ahead of Tuesday night with the first, and likely only, presidential debate between Harris and Trump. With perceptions between the two candidates at the helm of the party tickets potentially shifting among voters, this could be a consequential opportunity for candidates up and down the ballot to accumulate support.