Nearly two-thirds of American voters believe the GOP tax plan favors the rich, a new poll found.

Sixty-four percent of American voters said the Republican tax plan would help the rich the most, while 24 percent said it would benefit the middle class, and 5 percent said it would benefit low-income people, according to a Quinnipiac University national poll released Tuesday.

Just 29 percent of the poll’s respondents approved of the plan, compared to 53 percent who disapproved.

The approval rating for the tax overhaul, which Senate Majority Leader Mitch McConnell has called a “once-in-a-generation opportunity,” was split along party lines, with 67 percent of Republicans approving it and only 10 who disapprove.

A sweeping 84 percent of Democrats disapprove of the plan. Only 6 percent approve it.

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From November 29 – December 4, Quinnipiac University surveyed 1,508 voters nationwide using landline and cell phone interviews. The margin of error of is 3.1 percentage points.

President Donald Trump’s approval rating sits at 35 percent, the poll found, down 3 points from November.

“Deeply unpopular and manifestly unfit for the job. That’s the harsh assessment of President Donald Trump, whose tax plan is considered built for the rich at the expense of the rest,” Tim Malloy, assistant director of the Quinnipiac University Poll, said in a statement.

National contempt for the GOP tax plan could be, in part, a manifestation of the yearslong trend the Quinnipiac poll has identified that the public has soured on the Republican party in general.

 In Dec. 2013, 47 percent of respondents to the poll said they preferred Republicans to win control of the U.S. House and Senate, compared to 42 percent who preferred Democratic majorities.

In the latest poll, those numbers reversed, with 50 percent saying they preferred Democratic control of the House and 51 preferring Democratic control of the Senate.

Democrats hope to capitalize in the 2018 midterms running against the unpopular Trump presidency and stagnation in the GOP-controlled Congress.