Trump's rally is Monday at a hangar by Williamsport Regional Airport in Montoursville. Trump is coming amid tensions with Iran, a growing trade dispute with China and the easing of tariffs on allies.
It's Trump's first visit to Pennsylvania this year.
Trump scored an upset win in Pennsylvania in 2016, albeit by less than 1 percentage point, and the state is part of his likeliest path to winning a second term in 2020.
Republican Fred Keller and Democrat Marc Friedenberg are vying to fill an open seat in a heavily Republican district.
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