It’s simple: In any assessment of the 2020 presidential race, Pennsylvania is critical.

It’s a swing state with 20 electoral votes, tied for fifth most, and, with Michigan and Wisconsin, was one of three traditionally blue states that tipped the 2016 election to President Donald Trump.

The president’s campaign, the main Super PAC backing him, and top Democratic groups have all targeted the Keystone State as one of the most important on the map — a vital piece of the “Blue Wall” that Trump fractured, and that could prove decisive.

So, fresh off Trump’s official reelection announcement Tuesday, what does he need to do to win Pennsylvania again? That’s more complicated.

The 2016 result was so excruciatingly close in the state — decided by 44,000 votes out of more than six million cast, less than 1 percent — that tiny shifts in any part of the electorate could change the outcome next year.

There isn’t one key factor. There are many.

  • If Trump’s strength in Rust Belt, working-class counties and rural areas recedes even a small amount, he could lose.

  • If Democrats continue to surge in the suburbs, that could doom Trump.

  • If Democratic voters in Philadelphia and Pittsburgh move closer to the historic turnout levels seen under Barack Obama, that could flip the state back.

  • Or if Trump manages to pull in voters who didn’t support him in 2016, he could repeat his win.

Public polling, and even Trump’s internal polling, suggests the president starts with an uphill climb. Pennsylvania voters disapproved of Trump’s performance by 54 percent to 42, according to a Quinnipiac University poll in May, which also found the president trailing potential challengers such as Joe Biden and Bernie Sanders.

“No one is under any illusion that it’s going to be easy,” said David Urban, a Republican lobbyist who advised Trump on Pennsylvania in 2016. “I have personally spoken to the president and he is prepared to put in the time and effort that is required to campaign, work hard, contest, ask for every vote in Pennsylvania just like he did last time.”

Interviews with more than a dozen elected officials, activists, political operatives, and analysts, combined with a review of recent election results reveal several distinct battlegrounds within the state, each of which could help decide not just the outcome in Pennsylvania, but the entire campaign.

Here are some of the places that could shape the results:

Rural ‘Trump Country’

To win Pennsylvania, Trump needs to hold on to the largely white, postindustrial counties and rural areas he won here in 2016.

Nationally, Trump has accelerated a political realignment: historically Democratic, small urban communities hit by economic change and rural areas shifting toward the Republicans, and traditionally Republican suburbs moving toward Democrats.

Pennsylvania has seen both.

Consider Erie County, one of the most drastic examples. Barack Obama easily won the county in the state’s northwest corner in 2012. Four years later, it turned narrowly red, thanks to a 21,000-vote swing toward Trump — nearly half of the margin that decided the entire state.

The switch mirrored swings in other counties such as Luzerne, which saw a 32,000-vote shift toward the GOP compared with 2012, Lackawanna (a 23,000-vote shift), Northampton (11,000 votes), and Westmoreland (16,000), to name just a few.

A Turn to Red in the Last Presidential Election

From the 2012 to the 2016 presidential elections, 63 of the state's 67 counties shifted more Republican in their vote margins.

SOURCE: Pa. Department of State