President Donald Trump made his case for tax reform on Wednesday, relying heavily on populist themes to tout a broad plan that claims to boost the American economy and deliver a “big fat beautiful paycheck” to the middle class.

“We’re here today to launch our plans to bring back Main Street by reducing the crumbling burden on our companies and on our workers,” Trump said in a speech inside a manufacturing plant in Springfield, Missouri. “The foundation of our job creation agenda is to fundamentally reform our tax code for the first time in more than 30 years.”

There were few new details about the plan, beyond the brief, one-page outline his administration unveiled in April that was heavily criticized as a boon for corporations and the wealthiest Americans.

Rather than providing specifics, Trump on Wednesday appeared to frame his pitch as a challenge for Congress to be responsible for fulfilling the goal of tax reform.

“I don’t want to be disappointed by Congress—do you understand me?” he said, in comments that appeared to echo his criticism for the Republican failure to repeal the Affordable Care Act.

“I think Congress is going to make a comeback—I hope so,” Trump continued. “I’ll tell you what, the United States is counting on it.”

He also singled out Sen. Claire McCaskill (D-Mo.), telling the crowd to vote her out of office if she did not support his push for tax cuts.