Voters head to the polls Tuesday in Pennsylvania’s 12th District to choose a new congressman, and Republican state Rep. Fred Keller is strongly favored in the deep-red district.

The race to replace GOP Rep. Tom Marino, who resigned in January, hasn’t garnered much national attention given the district’s partisan lean. Inside Elections with Nathan L. Gonzales rates the contest Solid Republican.

Still, the race could be an early test of both parties’ messaging ahead of 2020. President Donald Trump brought the national spotlight to the north-central Pennsylvania district with a Monday night rally, as Keller has sold himself as someone who would back the president’s priorities.

The Democratic nominee, Marc Friedenberg, has been stressing his rejection of corporate PAC money and his calls to improve infrastructure and protect Medicare and Social Security. 

Here are three things to watch after the polls close at 8 p.m., Eastern time:

1. The margin

Unlike past special elections, outside groups and the national parties have not engaged in this race, which is a sign that it is not expected to be competitive. Friedenberg, an assistant college professor, is hoping to narrow his margin from November, when he lost to Marino by 32 points, 66 percent to 34 percent.

Marino won re-election even after he had to withdraw his name from consideration to head the Office of National Drug Control Policy. His move followed reports that a law based on a bill he sponsored hindered the Drug Enforcement Administration’s ability to target opioid manufacturers.

Trump would have carried the 12th District by 36 points in 2016, winning 66 percent of the vote, had the new congressional lines been in place. If Tuesday’s margin is dramatically narrower, that could be an early warning sign for Republicans heading into 2020.

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2. Do independents turn out?

Independent voters were critical to Democratic victories in competitive districts in 2018, and it’s unclear whether they will turn out in this special election. The race takes place on the same day as the state’s municipal primaries, which are closed to those not affiliated with a political party.

Fourteen percent of voters in the 12th District are registered with no party or with a third party. Republicans have a significant advantage here, with 55 percent registered with the GOP. Thirty-one percent of 12th District voters are registered Democrats.

3. Does Trump take credit?

Keller has long been expected to win this race, but Trump’s decision to travel to the district could signal that he is looking to take some credit for the Republican’s likely win.

Trump’s rally on the eve of the special election is reminiscent of his trip to Pennsylvania’s 18th District ahead of a special election there in March 2018, when GOP state Rep. Rick Saccone lost to Democrat Conor Lamb in a district the president had carried by 20 points in 2016. Lamb’s upset win was a precursor to Democratic victories across the country that November. 

Trump added to his last-ditch push for Keller by recording a robocall for the GOP nominee. He touted the unemployment rate and said the steel industry was “roaring back like never before.”

“In Congress, Fred will work with me to lower your taxes, secure our border, and strengthen our military, unlike Nancy Pelosi and the radical liberal socialist Democrats who only obstruct and oppose our tremendous accomplishments,” Trump said in the call, according to Keller’s campaign.

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