Washington CNN  — 

After hitting an all-time low last month, President Donald Trump’s approval rating has taken an upward swing – as public support for his tax plan also shot up, according to a new poll.

WASHINGTON, DC - JANUARY 30:  U.S. President Donald J. Trump delivers the State of the Union address as U.S. Vice President Mike Pence (L) and Speaker of the House U.S. Rep. Paul Ryan (R-WI) (R) look on in the chamber of the U.S. House of Representatives January 30, 2018 in Washington, DC. This is the first State of the Union address given by U.S. President Donald Trump and his second joint-session address to Congress.  (Photo by Win McNamee/Getty Images)

Forty-two percent of Americans now approve of the President’s job performance, according to a Monmouth University poll released Wednesday. That is up 10 percentage points from December 2017, when he registered a 32% approval rating – Trump’s lowest mark ever in the monthly poll.

The poll also showed growing public support for last month’s GOP tax reform plan, which was passed through both houses of Congress on party lines with overwhelming Republican support and signed by Trump in December. The plan’s approval rating now stands even, with 44% of Americans approving and 44% disapproving – a huge improvement from last month, when only 26% approved of the plan and 47% disapproved.

The number of people polled who say the plan will make taxes go up has fallen 14 percentage points, down to 36%, and the number who say it will make taxes go down has climbed 10 percentage points, up to 24%, Monmouth reported.

Other polling corroborates this positive momentum. The latest CNN poll showed Trump’s approval rating up from 35% to 40% since December. A Fox News poll showed him up from 38% to 45% among registered voters since October.

Despite the improvement, half of Americans, 50%, still disapprove of the President’s job performance, according to Monmouth.

The boost in his approval rating isn’t the only good news for Trump more than a month after he signed his signature tax legislation into law. A majority of Americans – 55% – say the President has been at least somewhat successful in getting Congress to pass his legislative agenda, up from 42% last month.

Just more than 7 in 10 Americans (71%) say Trump’s agenda has focused at least a little on the issues important to average Americans.

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The polling bump also applies to the Republican Party in general, showing a tightening in voter trends in favor of the GOP when looking ahead to 2018. After having a 15-point lead on a generic congressional ballot question last month, Democrats now hold a mere 2 percentage point edge, at 47% to 45% among registered voters, according to this new poll.

“The generic congressional ballot is prone to bouncing around for a bit until the campaign really gets underway later this year,” said Patrick Murray, director of the Monmouth University Polling Institute, in a release accompanying the poll. “But Democrats who counted on riding public hostility toward the tax bill to retake the House may have to rethink that strategy.”

This Monmouth University poll was conducted January 28-30, 2018, among 806 adults. It has a margin of sampling error of ±3.5% pts.