The same poll, conducted one month apart, shows which presidential candidate is gaining momentum in key states

SCRANTON, Pa. — With less than four weeks until Election Day in November, new polls in three crucial battleground states suggest former President Trump is making gains but remains in a neck-and-neck race with Vice President Kamala Harris.

Harris, the Democratic presidential nominee, has a 49% to 46% lead in Pennsylvania over Trump, the Republican standard-bearer, according to Quinnipiac University polls.

But the former president leads the vice president 50% to 47% in Michigan and 48% to 46% in Wisconsin.

Harris' three-point lead in Pennsylvania has shrunk from a 6-point lead in Quinnipiac's previous poll a month ago.

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Former President Trump and Vice President Kamala Harris appear during their first and likely only debate on September 10 in Philadelphia. (Doug Mills/The New York Times/Bloomberg via Getty Images)

The results in Michigan, where Trump has a three-point lead, represent a change from last month, when the Quinnipiac poll showed Harris leading by five points.

And in Wisconsin, where the new poll gives the former president a 2-point lead, it represents a slight change from September, when the vice president had a 1-point lead.

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“That was then, this is now. The Harris post-debate starburst is fading as Harris slips slightly in the Rust Belt in recent weeks,” said Quinnipiac University poll analyst Tim Malloy.

Pennsylvania, Michigan and Wisconsin, along with Georgia, North Carolina, Arizona and Nevada, had razor-thin margins that determined President Biden's White House victory over Trump in 2020. And the seven states will likely decide whether Trump or Harris wins the 2024 presidential election.

Former President Trump speaks to the crowd at a rally in Butler, Pennsylvania, on Saturday. The rally was held at the same location as the July 13 assassination attempt on Trump. (Matthew McDermott for Fox News Digital)

Pennsylvania, Michigan and Wisconsin are also the three Rust Belt states that form the Democrats' so-called “Blue Wall.”

The party reliably won all three states for a quarter century before Trump narrowly won them in the 2016 election and won the White House.

Four years later, in 2020, Biden narrowly defeated all three states to bring them back into the Democratic fold and defeat Trump.

Both the Democratic and Republican presidential candidates and their running mates made repeated stops in the three states this summer.

Trump is holding campaign events in Scranton and Reading, Pennsylvania, on Wednesday. And Harris returns to Pennsylvania early next week for a stop in Erie.

Vice President Kamala Harris speaks to the Economic Club of Pittsburgh on the campus of Carnegie Mellon University in Pittsburgh on September 25. (AP Photo/Gene J. Puskar)

Both candidates have also been campaigning in Michigan and Wisconsin in recent days.

All three states also have crucial Senate races that will likely determine whether the GOP regains the majority in the chamber.

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In Pennsylvania, the Quinnipiac University poll shows Democratic Sen. Bob Casey leading Republican challenger Dave McCormick 51% to 43%.

According to the poll, the race to replace Democratic Sen. Debbie Stabenow of Michigan, Democratic Rep. Elissa Slotkin and former Rep. Mike Rogers is tied at 48%.

And in Wisconsin, Democratic Senator Tammy Baldwin is leading Republican challenger Eric Hovde 50% to 46%, according to polls.

The Quinnipiac University polls were conducted Oct. 3-7. 1,412 likely voters in Pennsylvania, 1,007 likely voters in Michigan and 1,073 likely voters in Wisconsin were surveyed.

The sampling error in Pennsylvania is plus or minus 2.6 percentage points. In Michigan it's plus or minus 3.1 percentage points. And in Wisconsin it's plus or minus 3 percentage points.

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