New Jersey's top state lawmaker and once-leading advocate for raising taxes on wealthy residents said Thursday that a millionaires tax is now the "absolute last thing" he will consider.

"It's the absolute last thing that I'm willing to look at," state Senate President Stephen Sweeney, D-Gloucester, told reporters in Trenton. "It's too much right now. Absolutely last resort."

Only three months ago, on the morning after fellow Democrat Phil Murphy captured the governor's office, Sweeney tweeted that the "long-overdue millionaires tax" would be "the first bill we pass in January."

But Thursday's 180-degree reversal has been building since then, with the south Jersey Democrat cautioning that the recent Republican-backed federal tax reform had complicated matters locally.

Sweeney's new statement was his sharpest rebuke yet of the tax promise that for eight years topped Democrats' policy wish list and was expected to lead their progressive agenda with Democrats in control of the state Legislature and governor's office.

Under Sweeney's leadership, the Legislature passed and put a millionaires tax on former Gov. Chris Christie's desk five times since 2010. And each time, the Republican governor killed the tax hike.

In his final veto of the tax in 2015, Christie said the Legislature must be "deaf and blind" to the consequences of raising taxes for New Jersey's economy.

The state's personal income tax rate tops out at 8.97 percent on income over $500,000. A millionaires tax would create a new bracket for income over $1 million, taxed at 10.75 percent.

Sweeney's turnaround on the millionaires tax now puts him at odds with New Jersey's newest governor, who's counting on the more than $600 million in new tax dollars to underwrite major campaign promises, like fully funding k-12 education and government worker pensions.

Murphy stands by the call for higher taxes on residents making more than $1 million a year. But the governor needs the state Legislature to pass the proposal before he can sign it.

That means he needs Sweeney, the man who controls votes in the Senate, on board.

But Sweeney says the federal tax reform that President Donald Trump signed into law in December added an unforeseen twist, and New Jersey can't afford to tax its high earners out of the state.

The federal tax law eliminated a valuable deduction for New Jerseyans: the state and local tax deduction. That tax break took the edge off the state's highest-in-the-nation property taxes and highly progressive personal income taxes.

The law caps the tax break at $10,000 for property taxes and state income taxes combined, a threshold many New Jerseyans easily surpass. The average property tax bill here in 2016 was $8,549.

Sweeney says the state can't risk hitting residents with another tax punch and driving them out of the Garden State. Instead, he wants lawmakers to conduct a sweeping review of the state and local tax structure.

"Before we talk about raising any taxes, we have to talk about the cost of government," Sweeney told NJ Advance Media this week. "What Trump did to New Jersey made me do a complete about-face and say, hold up. I am not rushing to do taxes. I'm not gonna run in an do something that's gonna cause even more problems for the economy."

It was a topic of interest as state Senate and Assembly Democrats convened a rare joint caucus at the Hyatt Regency in New Brunswick on Tuesday.

At the meeting, billed as a get-to-know-you event at the start of a new legislative session, top Democrats presented internal polling they commissioned from national pollster Mark Mellman, who worked for former U.S. Senate Majority Leader Harry Reid, two sources told NJ Advance Media.

Legislative leaders said polling showed they should proceed with caution on a millionaires tax, as voters will support it initially but ultimately forget who raised taxes on whom, said the sources, who requested anonymity because they didn't want to talk publicly about a private meeting.

A 2017 Quinnipiac University poll found seven in 10 New Jersey voters were in favor of raising taxes on those with income over $1 million to raise cash for the public pension system.

But Murphy says he's not backing down. On Monday, the governor said he's "still committed -- both on the revenue side and on the investment side -- to the things we talked about throughout the campaign."

"And that includes tax equity, investment in public education, etc.," Murphy said.

State Sen. Richard Codey, D-Essex, a former governor himself and Murphy's ally, said there's still support for the millionaires tax in the Senate.

"The only people affected would be people who make a million dollars a year, and the tax only starts on the first penny after a million dollars," Codey said.

New Jersey's wealthiest survived the last millionaires tax, which expired as Christie came into office, and they'll survive the next, added state Assemblyman Ralph Caputo, D-Essex.

"I think it's a logical step," Caputo said. "I didn't see anybody drop dead when we had the millionaires tax in effect when Christie came into office."

Steve Baker, a spokesman for the New Jersey Education Association, which endorsed Murphy and put millions behind Sweeney's Republican challenger this fall, said there's a desperate need for new revenue to fund education, and New Jersey finally has a governor "who has indicated he's willing to do it."

"We hope people will stand by the values they've long held and do the right thing," Baker said.

NJ Advance Media staff writer Matt Arco contributed to this report.

Samantha Marcus may be reached at smarcus@njadvancemedia.com. Follow her on Twitter @samanthamarcus.

Brent Johnson may be reached at bjohnson@njadvancemedia.com. Follow him on Twitter @johnsb01.

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