Wednesday’s meeting is expected to include Sen. Claire McCaskill (D-Mo.), a member of the Finance Committee who has  been critical of Trump’s approach so far. McCaskill has spent weeks pushing the White House to work more closely with Democrats on the tax plan, saying that a failure to work with Democrat doomed their efforts to make changes to health care rules.

But even though McCaskill is up for reelection in 2018 and comes from a state Trump won handily, she is digging in against the White House’s tax plan more than many of her colleagues, convinced voters will see it as a big handout for the rich.

During a meeting last week with constituents in Washington, Mo., McCaskill asked everyone to put a question on a slip of paper and drop it into a fishbowl.

The third question McCaskill plucked from the bowl asked simply, “Will you help get tax reform done this year?”

“I hope so. I would love to get tax reform done,” she said. “But here’s the issue. The issue is what is the tax reform bill? Now, I haven’t seen a final plan. We’ve seen an outline and the outline is very troubling to me.”

She explained that she’s “not interested in reducing taxes for the [wealthiest] 1 percent. I am very interested in reducing taxes to the middle class and to families that are living paycheck to paycheck. … That’s where my focus is.”

McCaskill then turned to notes on a lectern, telling the audience that she had asked staffers to determine how much money a Missouri family of four earning $50,000 would end up paying under the Republican proposal.

“Under the current law, their tax bill with the personal exemptions and the standard deduction and the child tax credit and the earned income tax credit, currently they’d pay $107 in taxes,” she said. But because the Republican plan would eliminate personal deductions, that same family would pay $887 in taxes if Trump gets his way.

Many in the room gasped.

“The family of four making $50,000 is going to pay more for taxes — that’s not middle-class tax relief,” she said, while noting that Republicans had not yet determined what they will do about the child tax credit.