President Trump has his eyes on Ohio.

“Get your co-workers, get everybody, and get out and vote. Got to get out and vote. And in your state, in Ohio, early voting has already begun and don’t wait,” the president urged his supporters this week as he held a rally at Dayton International Airport.

WHAT THE LATEST FOX NEWS POLL SAYS ABOUT THE BATTLE FOR OHIO

It was one of two stops Trump made Monday as he campaigned in the Buckeye State.

President Donald Trump speaks during a campaign rally at Eugene F. Kranz Toledo Express Airport, Monday, Sept. 21, 2020, in Swanton, Ohio. (AP Photo/Alex Brandon)

Trump’s partner on the GOP ticket, Vice President Mike Pence, campaigned in Zanesville, Ohio a week earlier.

Ohio has long played a crucial role in presidential elections. It was famously the state that put President George W. Bush over the top in 2004, as he won a second term in the White House.

President Barack Obama narrowly carried the state in 2008 and 2012. Four years ago, it appeared it would be another close contest. An average of the polls on the eve of the 2016 election indicated Trump with a 2.2 point edge over Democratic nominee Hillary Clinton. But Trump ended up swamping Clinton by 8 points, flipping the state from blue to red and winning Ohio’s 18 electoral votes.

Trump’s margin of victory was the largest by any presidential candidate in nearly three decades. Contributing to Trump's success was his targeting of free trade deals supported by Democrats. He specifically blasted the North American Free Trade Agreement, arguing that it had allowed auto and steel factories to flee Ohio, destroying part of the state’s economy.

Fast forward four years and Ohio – at the beginning of this presidential cycle  -- wasn’t expected to be a battleground in the White House race.

But an average of the latest public opinion polls in Ohio compiled by Real Clear Politics shows Democratic presidential nominee Joe Biden with a 3.3 point edge over the president. That includes a Fox News poll conducted Sept. 20-23 and released Thursday that had the former vice president topping Trump 50% to 45% among likely voters in Ohio.

“I always felt that 2016 was an anomalous result for Ohio,” Paul Beck, professor emeritus of political science at Ohio State University, told Fox News.

“Trump did very well in 2016 here in Ohio, and he had a lot of things going for him in Ohio, one of which was the unpopularity of Hillary Clinton,” said Beck, an expert on the state's political trends.

“Biden plays well in areas of Ohio, I think, where Trump did well in 2016, and that is particularly true in northeastern Ohio, where Trump cut into the normal Democratic advantage pretty heavily there …. particularly among white males. And I think Biden has more appeal to white males than Hillary Clinton did in 2016,” Beck said.

He also pointed to a decline in turnout among Ohio minority voters in 2016 -- most of whom vote Democratic – and suggested that won't be repeated in 2020.

Neither Biden or Democratic vice presidential nominee Sen. Kamala Harris have campaigned in person in Ohio during the general election. That’s a factor the president zeroed in on as he also slammed the latest polling in the state.

“I just saw that we’re tied in Ohio. I don’t think so,” Trump said Monday at a rally in the Toledo suburb of Swanton. “They’re not even campaigning in Ohio, come to think of it. Now, they’re fake polls. They’re almost as fake as the writers themselves. They’re all fake.”

Biden – and the president – will both be in Ohio on Tuesday as they face off for the first time in the general election at the first of three presidential debates. The showdown, which will be held at 9 p.m. ET in Cleveland, is being moderated by "Fox News Sunday" anchor Chris Wallace.

Iowa

Iowa, like Ohio, wasn’t expected to be a swing state at the start of the 2020 cycle.

Obama carried Iowa in 2008 and 2012, but Trump flipped it from blue to red four years ago, topping Clinton by 9 points.

But an average of the three latest polls in the Hawkeye State – all conducted in the last two weeks – has Biden and Trump deadlocked at 46%.

The president last stopped in Iowa in mid-August – on an official trip to survey storm damage. Pence returns for a campaign stop next week. Neither Biden nor Harris have made in-person stops in the state during the general election.

Pennsylvania

An average of the latest polls in the key battleground state of Pennsylvania compiled by Real Clear Politics indicates a close contest – with Biden edging the president by 4.3 points. That’s down slightly from a 5.5 point advantage a month ago.

The new average includes a Fox News poll released Thursday that showed the former vice president with 7-point lead over Trump.

Pennsylvania – along with Michigan and Wisconsin – had been carried by the Democrats in presidential elections for a quarter-century. But Trump narrowly edged Clinton in all three states four years ago, helping him win the White House. An average of the final polls on the eve of the 2016 election gave Clinton with a 2.2 point edge over Trump in the Keystone State, but Trump edged the Democrat by seven-tenths of a percent to capture Pennsylvania’s 20 electoral votes.

Biden – who was born and spent his first 10 years in Scranton, Pa. – retains strong ties to the state. During his three and a half decades representing neighboring Delaware in the Senate, he earned the nickname "Pennsylvania's third senator."

Biden kicked off his 2020 White House bid with events last year in Philadelphia and Pittsburgh, and he has made numerous campaign stops in the state in the past four months.