MU poll: Donald Trump approval rises, Bernie Sanders leads Dems as Wisconsin girds for 2020 campaign

Wisconsin is as polarized as ever, but three issues enjoy widespread support: Medical marijuana, Medicaid expansion and a boost in state aid for special education.

Those are just some of the fascinating nuggets from Wednesday's Marquette University Law School Poll of 800 registered Wisconsin voters.

It's the school's second survey of the year as poll director Charles Franklin digs into the political terrain ahead of the 2020 presidential campaign and looks at the state of play in Madison where Democratic Gov. Tony Evers faces a Republican-led Legislature.

Here are the four main takeaways.

Donald Trump and the Democrats

With Wisconsin looming as a battleground in 2020, every movement in Trump's approval is scrutinized. Since January's last poll, the president ticked up 2 points to 46% approval, compared with 52% disapproving his performance in office.

Just 28% say they will definitely vote to re-elect Trump next year, while 14% say they will probably vote for him.

Meanwhile, 8% say they will probably vote against the president and 46% say they will definitely vote against him.

It's far too early to handicap the Democratic presidential horse race.

So instead of asking voters to say which candidate they would vote for in a hypothetical primary, Franklin asked them to rate every candidate as either a top choice, an acceptable choice or someone they would not vote for or had not heard enough about.

As a top choice, Bernie Sanders of Vermont had 32% while former Vice President Joe Biden had 29%.

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Others with double-digit percentages include U.S. Sen. Elizabeth Warren of Massachusetts (17%), U.S. Sen. Kamala Harris of California (11%) and former Texas congressman Beto O'Rourke (10%).

Mueller report

The investigation is over, the report hasn't been made public, but the public is trying to make sense of special counsel Robert Mueller's investigation of Russian meddling in the 2016 election.

Based on what they have heard, 67% have a great deal or some confidence that the investigation was fair and impartial while 24% have little or no confidence in the probe. Since October, confidence in the investigation rose among Republicans and independents and declined among Democrats.

Sixty percent think that Russia interfered with the election. Fifty-three percent say the Trump campaign did not collude with Russia to influence the election's outcome, while 35% say the campaign did.

Forty-five percent say that Trump tried to obstruct the investigation and 45% say he did not.

Thirty-nine percent say the investigation cleared Trump of any wrongdoing but 54% say questions remain about his behavior.

Evers and the Republican Legislature

The public is still getting to know the new governor. In January, 38% didn't have an opinion of him, while 39% approved of his performance and 22% disapproved.

The new numbers: 47% say they approve of Evers'  performance, while 37% disapprove and 15% don't have enough information to render a verdict.

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The Republican-led Legislature has 50% job approval and 38% disapproval. But on a key question of cooperation, the public appears to side with Evers.

Forty-eight percent say Evers is trying to cooperate with the Legislature while 37% say he's not interested. Only 25% say the Legislature is trying to cooperate with the first-year governor and 57% say the Legislature is not interested. 

On the issues

By overwhelming margins, the public sides with Evers on three issues.

Eighty-three percent back the legalization of medical marijuana. Seventy percent say the state should accept federal funds to expand Medicaid. Seventy-four percent favor a "major increase" in state aid for special education.

But another Evers push, to increase gas taxes, gets a thumbs down. Just 39% support increases in gas taxes and fees to pay for more road and highway work while 57% prefer the current rates.

Only 41% support a freeze in enrollment in private voucher schools and suspending charter school expansion, while 46% oppose the effort.

The public appears open to change on criminal justice issues, including 71% in favor of the elimination of mandatory minimum sentences and 88% in support of expanded job training for prisoners.

The poll of 800 Wisconsin registered voters was conducted Wednesday through Sunday, with a margin of error of plus or minus 4%. Issue questions were asked on a half sample with a margin of error of plus or minus 5.7%.

Democrats and independents who lean Democratic or are pure independents were asked about Democratic presidential candidates. That sample had a margin of error of plus or minus 5.6%.