President Trump leaves little doubt about how great his tax overhaul is going to be when he is in front of crowds, urging them to pressure Congress to pass it.

"Does anybody in this room mind getting a massive tax cut?" Trump said last week at a White House reception for Hispanic Heritage Month.

After the audience shouted, "No," Trump continued: "Does anybody object to paying less taxes?" Another loud "No" followed.

But what the president did not mention is that some people — one study said 1-in-5 people making between $86,100 and $149,400 — will end up paying more. The challenge Congress faces in passing the tax package is getting lawmakers whose constituents are paying more to vote for it.

Right now, Trump's advisers and his supporters in Congress are working to downplay any mention of paying more, even though that is an inevitable part of the kind of overhaul they are planning, which involves eliminating deductions and credits to produce lower rates overall.

Any tax bill is a tradeoff: It needs to raise taxes in some areas to generate revenue to offset the tax cuts that reduce the government's revenue.

"If you are a tax writer on the Hill, the president's rhetoric must drive you crazy because you know you can't write a tax bill that lives up to that," said Robert Bixby, executive director of the Concord Coalition, a non-profit that crusades against increased debt.

"I don’t think we can have the Oprah tax reform, this idea of, 'Everybody gets a car, the keys are under the seat,'" Bixby said. "There might be something unpleasant under the seat also."

Maya MacGuineas, president of the Committee for a Responsible Federal Budget, said delivering tax cuts for everyone would only work if there is a big budget surplus and low debt.

"That's the opposite of the fiscal environment they have now," she said. "If you want reform, some taxes go up, and some go down."

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Trump's top economic adviser, Gary Cohn, sought to portray the possibility someone would be hit with a higher tax bill as an anomaly when he described the plan in the White House briefing room last month.

"I cannot guarantee that," Cohn said when asked if everyone will get a tax cut. "You could find me someone in this country that their taxes may not go down. Remember, we have 50 states. We have counties. We have cities. We have long-term capital gains. We have short term capital gains. We have all different types of structures in the tax code."

Exactly how each taxpayer will be affected is not yet known, because the "unified framework" for taxes that Trump and Republicans in Congress released Sept. 27 left out key details, including exactly which tax deductions and credits would be eliminated.

The House Ways and Means Committee and Senate Finance Committee will not start filling in those details until both houses agree on a budget resolution that specifies how much tax reform could cost and sets instructions to prevent a filibuster in the Senate.

Supporters of the tax package have gone from saying lower rates would be fully offset by cutting deductions and credits to saying it would be offset by future economic growth, a stance that MacGuineas and Bixby said is unsupportable and one that could derail the tax plan's passage.

"Unless it reduces deficits ... with reasonable and responsible growth models, and unless we can make it permanent, I don’t have any interest in it," Sen. Bob Corker, R-Tenn., said last week at a Senate Budget Committee hearing. The committee's budget resolution calls for a tax package that would reduce revenues by $1.5 trillion over the coming decade.

Using data from earlier plans outlined by House Republicans to fill in some of the blanks in Trump's plan, the nonpartisan Tax Policy Center released a preliminary estimate of how people at different income strata would be affected.

On average, the study found people in every income group will see lower taxes, but there are winners and losers within income groups. Even in the middle class, 14 percent to 20 percent of taxpayers could end up paying an extra $1,000 or more under Trump's plan.

For example, for those earning between $48,600 and $86,100, about 85 percent of taxpayers would see an average cut of $940. But 13.5 percent would see a tax increase, averaging $1,000, the Tax Policy Center found, mostly because they would no longer be able to claim deductions and exemptions they are using to lower their tax bills now.

Among those earning between $86,100 and $149,400, 79 percent would get a tax cut averaging $1,860, while 20 percent would pay an extra $1,790 on average.

Eliminating deductions will be a political problem for Congress. New Jersey, which has the highest average property taxes in the country, would be hit hard by ending the ability to deduct state and local taxes, for example.

"I am going to do what I can to rally states like New Jersey, New York, Pennsylvania, California, Illinois and Connecticut," said Rep. Tom MacArthur, R-N.J. "It's not fair to give the entire country a tax break on the backs of the citizens of these six or seven states ... who, by the way get the least back as a percentage of what we pay."

To keep pressure up to pass the tax plan, a group affiliated with House Speaker Paul Ryan, the American Action Network, has funded a campaign of robocalls and cable television ads in targeted congressional districts around the country, including those of MacArthur and fellow New Jersey Republican Leonard Lance.

Liberal groups, meanwhile, are trying to convince the public to look beyond the tax bill.

If Congress relies on a projected surge of economic growth to pay for tax cuts and that surge does not happen, Congress will look for places to cut spending when deficits start to grow in the future, said Frank Clemente, director of the liberal group Americans for Tax Fairness.

"The reality is, the way the Republicans structured their plans, people at $50,000 a year are going to get maybe a buck a day, not enough to by a cup of coffee," Clemente said. "Is it worth getting that extra money if ... it's going to jeopardize retirement security, health care, help to send their kids to college, the roads and bridges everybody agrees we need?"