President Trump is speaking at a “Make America Great Again” rally in Mosinee, Wis., to rouse support for Gov. Scott Walker, a former presidential campaign rival who is running for re-election against Democratic challenger and state schools superintendent Tony Evers.

Trump’s visit to Wisconsin comes the same day as an array of Trump critics around the country were sent potential explosive devices. Trump said Wednesday afternoon that “the safety of the American People is my highest priority” and emphasized that “the full weight of our government is being deployed to conduct this investigation and bring those responsible for these despicable acts to justice.”

Trump’s rally is also aimed at aiding state Sen. Leah Vukmir — who is trailing incumbent Democratic U.S. Sen. Tammy Baldwin — and comes two days after he held a large rally in Houston for Texas Sen. Ted Cruz, another former presidential primary challenger.