HARRISBURG, Pa. (CBS/AP) — President Donald Trump is coming to the battleground state of Pennsylvania for a rally hours before voters in a congressional district in the northcentral part of the state pick a new representative to go to Washington. He also went after two Democratic presidential hopefuls on Twitter on Monday.

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.

Trump took shots at Sen. Bernie Sanders and former Vice President Joe Biden on Twitter on Monday morning.

“Looks like Bernie Sanders is history. Sleepy Joe Biden is pulling ahead and think about it, I’m only here because of Sleepy Joe and the man who took him off the 1% trash heap, President O! China wants Sleepy Joe BADLY!” Trump tweeted.

Republican Fred Keller and Democrat Marc Friedenberg are vying to fill an open seat in a heavily Republican district.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)