Seven key swing counties, known with some exceptions as “Bellwether Counties,” have consistently sided with the winning presidential candidate for decades.

They are Door County, Wisconsin; Kent County, Mich.; Vigo County, Indiana; Clallam County, Washington; and Bucks, Erie and Northampton counties in Pennsylvania.

In some, Trump won or improved his performance compared to 2020. Other counties have chosen Harris, who is expected to lose the race in 2024.

Here's how these battleground districts voted in Tuesday's election.

Bucks County, Pennsylvania

With a reporting rate of 98% as of Wednesday morning, Trump led in Bucks County, a predominantly suburban county north of Philadelphia, by just 512 votes. If Trump's 49.58% lead over Harris' 49.45% holds, it would be the first time a Republican has won the county since 1988. Biden beat Trump by four points in 2020.

According to the Fox News Decision Desk, Trump is expected to win Pennsylvania.

Erie County, Pennsylvania

In Erie County, Trump is leading with 50.26% of the vote, compared to 48.82% for Harris. Erie is located in the extreme northwest of Pennsylvania on Lake Erie, is predominantly rural and has a significantly smaller population.

That's a change from 2020, when Biden won the county by one percentage point.

Northampton County, Pennsylvania

Trump is also ahead in Northampton County with 50.63% of the vote, where Harris received 48.40%. Northampton, in eastern Pennsylvania, is a suburb and home to Lehigh University, a private research university.

Biden won Northampton by less than a point in 2020.

Berwood Yost, the director of the national polling group Center for Opinion Research, said all three Pennsylvania counties reflect many of the key demographic characteristics such as racial composition, education levels and population density make Pennsylvania so competitive.

“Both campaigns see the path to the White House through Pennsylvania,” Yost said, adding that the path to victory in Pennsylvania runs through Bucks, Erie and Northampton counties.

Biden won Pennsylvania overall in 2020 by a narrow margin of 1.17 percent.

Door County, Wisconsin

Door County, Wisconsin, broke from its usual front-runner status Tuesday evening as 50.56% of voters chose Harris and 48.33% chose Trump, according to unofficial results Wednesday morning.

This was in contrast to the state as a whole. According to Fox News, Trump was the winner in Wisconsin with 49.75% of the vote, compared to 48.8% who went for Harris.

In 2020, Biden received 50% of the vote in Door County, while Trump received 48.6% there. Biden carried Wisconsin to 49.6% overall while Trump got 48.9%, and the Democrat won the 2020 general election.

Kent County, Michigan

In Kent County, Michigan, 51.53% of voters chose Harris while 46.69% chose Trump. As of Wednesday morning, Trump is leading in Michigan with 50.09% of the vote to Harris's 48.09%, but the Fox News Decision Desk has not yet decided the race.

VOTERS IN SEVERAL STATES HAVE PROPOSED TO APPROVE CONSTITUTIONAL AMENDMENTS THAT PROHIBIT NON-CITIENTS FROM VOTING

Kent is a traditionally conservative county that has moved into contested territory in recent years. Kent's chosen candidate has also won Michigan and the general election in the last three presidential elections.

In the 2020 election, Biden won 52.1% of the vote in Kenty County, while Trump won 45.9%. This year, Biden led Michigan with 50.6% of the vote, while Trump received 47.9%.

According to WOOD-TV, this was the first time since Lyndon Johnson's re-election victory in 1964 that more than half of Kenty County's votes went to the Democratic candidate.

“Traditionally, Kent County was a Republican-leaning county and its dominant political culture was Reagan-Bush conservatism in the spirit of Gerald Ford, but that began to change around the (Barack) Obama years,” Whitt Kilburn said , a political science professor at Grand Valley State University, told WOOD-TV that he blames the change on a population boom and suburban development outside Grand Rapids.

A Democratic presidential candidate won Kent County for the first time in more than 40 years in 2008, when a majority of voters went for Barack Obama.

According to WOOD-TV, despite his victory in the general election and winning the Michigan vote in the 2012 election, Obama lost Kent County to Mitt Romney by 8 percentage points.

Kilburn credited Trump with ensuring Kent County remains purple territory.

“For the most part, Trump has been pretty clear. He rejects Reagan-Bush conservatism, and that can be applied to Ford as well…pillars of moral traditionalism, commitment to free trade, commitment to strong military alliances,” Kilburn told HOLZ-TV. “MAGA conservatism is presented to voters as an alternative, and an alternative that is radically different from the ideas of conservatism.”

Vigo County, Indiana

Trump won Vigo County, Indiana, with 58.08% of the vote, while Harris received 39.96%. The Republican presidential candidate also won statewide, receiving 59.08% of the vote, compared to 39.20% for Harris.

FOX NEWS VOTER ANALYSIS: HOW TRUMP WON BACK THE WHITE HOUSE

Matthew Bergbower, a political science professor at Indiana State University, described a lead district as a “microcosm of the nation” in terms of policy preferences.

However, his county, Vigo County in Indiana, moved vote for Donald Trump In 2020, it has voted for the winning candidate in every election since 1952.

Clallam County, Washington

In In Clallam County, Washington, Harris received 54.29% of the vote while Trump received 43.90%. Washington state also gave the Democratic presidential candidate 58.62% of the vote, while Trump received 39.10%.

Prior to the 2024 race, Clallam County was the only county to vote for the winning presidential candidate in every election since 1980.

In 2020, Biden led Clallam County with 50.4% of the vote, while Trump received 47.0%. Biden led Washington state in 2020 with 58.4% of the vote, while Trump received 39.0%.

Before Tuesday, the people of Clallam County were proud of their history as the “last leading county” in America.

CLICK HERE TO GET THE FOX NEWS APP

Pam Blakeman, chairwoman of the Clallam County Republicans, previously told Fox News Digital that she thinks the election “will be close in our county, but I see it trending toward Trump,” pointing out good Republican turnout and a ground game that she said is “the most active I’ve ever seen.” Still, Ben Anderstone, a progressive Washington political consultant, told Fox News Digital that “a Trump victory in Clallam County would be a bit of a surprise at this point.”

In the 2024 election, the largest swing state, Pennsylvania, gave Trump a victory with 50.78% of the vote, while Harris received 48.26%. And Trump also carried the state's three most important counties.

Fox News' Peter Pinedo contributed to this report.