WASHINGTON — With the clock ticking down to an epic House vote Thursday on the GOP tax bill, President Trump’s budget director took aim at high-tax, high-cost states like Connecticut that benefit from state and local tax deductions — which Republicans want to reduce or cut altogether.

“Whose fault is that?” Mick Mulvaney said when asked about predictions that loss of state and local deductions, known by the acronym SALT, would wreak havoc on middle-class taxpayers and state governments in Connecticut and similar states like New York and New Jersey.

“Is it the federal government’s problem that Connecticut is having such difficulty?”

Mulvaney, who as head of the White House Office of Management and Budget is one of President Trump’s point men on taxes, said he was optimistic the Republican tax plan ultimately would win congressional approval.

“The atmosphere is pretty positive,” he said.

But the atmosphere thickened late Tuesday with reports that Republican senators are considering a roll-back of Obamacare’s individual mandate — the requirement that all must have health insurance or face a tax penalty — as a way of paying for $1.5 trillion in tax cuts in the bill.

Mulvaney’s outburst against Connecticut and other such states followed the parameters of Red state/Blue state, Democratic/Republican divides on how best to foster a new, fair and equitable tax system.

The House is expected to vote on its version of the bill on Thursday. It varies from the Senate version in important ways, but both seek to double the standard deduction up to $24,000 per couple, soften or eliminate the estate tax and reduce the corporate tax from 35 percent to 20 percent.

The House bill would limit the mortgage interest deduction on new home loans to $500,000 while the Senate bill would keep the current $1 million cap in place.

The Senate bill would eliminate the SALT deduction entirely, while the House bill would eliminate it only for state income tax payments while capping property tax deductions at $10,000.

Loss of the SALT deduction has been a major rallying cry in opposition for Connecticut Democrats.

“Many citizens of Connecticut will see their taxes increase,” said Rep. Jim Himes. “Our most economically productive states are getting screwed by this deal in the service of handing a huge amount to corporations in the form of a 20-percent tax rate.”

To counter Republicans, Democrats have relied upon Connecticut’s status as a donor state — one that gets back 83 cents for every dollar it sends to Washington. A report last year by New York State Comptroller Thomas DiNapoli found that Connecticut had the nation’s highest per capita contribution to the federal treasury at $16,052. Mississippi had the lowest at $5,557.

Connecticut Democrats also have argued that loss of SALT deductions would only add to that inequity.

Mulvaney rejected the idea that Connecticut, as a donor state, would be subject to unfair double taxation if SALT deductions are eliminated or substantially reduced.

“As a taxpayer, I don’t care what the state gets,” Mulvaney said. “I care about my taxes. And one of the things I should care about is making sure I’m paying a tax that’s fair.”

The fairest comparison, he said, is not whether states like Connecticut are, in effect, subsidizing states like Mississippi or South Carolina that get back substantially more than a dollar for each tax dollar sent to Washington.

Rather, he said, it is what individuals of equal economic means pay in taxes if they live in a low-tax state like South Carolina, compared with a high-tax state like Connecticut.

“If I’m paying more fed tax than you are, I’m subsidizing your high tax existence,” he said.

Rep. Elizabeth Esty scoffed at Mulvaney’s equations.

“He’s flat wrong on the donor-state argument,” she said. “Government provides for things individuals can’t pay for themselves, things we value but it takes the organizational ability of government to provide. We choose to tax to provide things, but when more of our tax dollars go into fed kitty, those dollars would not be available to us to pay for hospitals, schools, roads and other needs

“Why should Connecticut pay for Floridians who live in hurricane alley?” she said. “We pay for agricultural subsidiaries. And I don’t see Mulvaney talking about government subsidies of oil and gas.”

In their political calculus, Republicans are framing their respective bills as benefiting the middle class by encouraging use of the doubled standard deduction in place of itemizing.

But in a state like Connecticut where middle-class couples easily could make $100,000-plus annually, itemizing — and thereby using the SALT deductions — often is a crucial part of the affordability factor that goes into home buying and family raising.

“Republicans should stop trying to jam this outsourcing, job-killing, corporate giveaway bill through Congress and work with Democrats on a tax plan that puts middle class families first,” said Rep. Rosa DeLauro.