Harris and Trump are dueling on the crucial battlefield of the “blue wall.”

MILWAUKEE – Vice President Kamala Harris and former President Trump will hold competing rallies around the same time Friday night, just a few miles apart in battleground Wisconsin's largest city.

With just four days until Election Day, the Democratic and Republican presidential candidates are making their final stops in Wisconsin, where nearly all recent opinion polls point to a margin of error race between the two candidates.

“As of this weekend, the way to predict the winner is to flip a coin. That’s how close it is,” Mordecai Lee, professor emeritus at the University of Wisconsin-Milwaukee, told Fox News.

Two days after Harris and Trump held competing rallies in Wisconsin — the vice president stopped in Madison, the state capital, while the former president was in Green Bay — they will hold dueling rallies again, this time in the same city.

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Former President Trump gestures after speaking at a campaign rally at the Resch Center in Green Bay, Wisconsin, on Wednesday. (AP Photo/Julia Demaree Nikhinson)

Trump's event will be held at the Fiserv Forum in Milwaukee, where he accepted his party's presidential nomination during the Republican National Convention in July. Harris will be a few miles away to attend a campaign rally at the Wisconsin State Fair Park Exposition Center.

The former president will come to Wisconsin from Michigan, another key battleground, where he held campaign events on Friday.

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Harris' rally in Milwaukee – which will also include popular rapper and songwriter Cardi B speaking – will be her third Wisconsin event of the day. That afternoon she stopped by a union hall in Janesville.

When a group of union members began chanting “Madam President,” Harris responded, “Not yet! Four days.”

The vice president also argued that “Donald Trump was no friend of workers.”

Vice President Kamala Harris speaks during a campaign rally in Janesville, Wisconsin, on Friday. (AP Photo/Charles Rex Arbogast)

The vice president then traveled to Appleton to lead a rally at a school.

The Democratic and Republican Party vice presidential candidates — Minnesota Gov. Tim Walz and Sen. JD Vance of Ohio — have both crisscrossed Wisconsin, and key surrogates — including former Presidents Obama and Clinton for Harris — are parachuted in dropped out of the Badger State.

Both campaigns and their coordinated committees and super PACs have also flooded Wisconsin's airwaves with television ads in the final stretch before Election Day next week.

Wisconsin, along with Michigan and Pennsylvania, are the three Rust Belt states that form the so-called “blue wall” of the Democrats.

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Democrats reliably won all three states for a quarter-century before Trump narrowly won them in the 2016 election over Democratic Party nominee Hillary Clinton to win the White House.

Four years later, in 2020, President Biden narrowly defeated all three states to bring them back into the Democratic fold and defeat Trump. In Wisconsin, Biden led the state by just over 20,000 votes out of more than 3.2 million cast.

A close race could likely come down to voter turnout in Wisconsin.

Former President Trump and Vice President Kamala Harris. (Getty Images)

The Harris campaign highlights that they have over 50 offices in 43 counties across the state and 250 coordinated full-time staff on site.

They emphasize that they knocked on more than 1.5 million doors in the fight for Wisconsin's ten electoral votes.

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Former Green Bay Packers quarterback Brett Favre speaks during a campaign rally for former President Trump at the Resch Center in Ashwaubenon, Wisconsin, on Wednesday. (Tork Mason/USA TODAY NETWORK-Wisconsin)

The Trump campaign, highlighting the pro-football rivalry between the Green Bay Packers in Wisconsin and the Vikings in neighboring Minnesota, took aim at the vice president.

“Kamala Harris doesn’t know the first thing about Wisconsin – she picked a Vikings fan as her running mate. Wisconsin voters are already rooting for President Trump, as evidenced by his lead in the polls, leading to early turnout, and that's big.” Support from hometown favorites including Hall of Famer Brett Favre and Wisconsin's former Governor Tommy Thompson,” Trump campaign national press secretary Karoline Leavitt argued in a statement to Fox News.

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Lee, who has been involved in Wisconsin politics for nearly five decades, noted the extensive attention his home state receives.

“We feel like we are the ones who are going to choose the next president,” he said.

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