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For people who really believed President Donald Trump could be toppled by a significant primary challenge in the 2020 election, a new poll from NBC News and the Wall Street Journal should set them straight: 90 percent of Republicans polled think Trump is doing a great job as president.

The poll, conducted after the April 18 release of special counsel Robert Mueller’s report on Russian meddling in the 2016 election, suggests that the report hasn’t changed many minds about the president. Less than a third of the respondents believed the Mueller report exonerated Trump from charges that his campaign colluded with the Russians to influence the outcome of the race against Hillary Clinton. But views on the report continue to filter through a hyperpartisan lens: nearly 70 percent of Democrats think the report failed to clear the president of wrongdoing, while only 11 percent of Republicans see it that way. These numbers have been pretty consistent for the past year, according to NBC, even though Trump’s signature domestic achievement, his massive tax cut bill, remains highly unpopular. The poll shows that the tax cut is even less popular with voters than Obamacare, which had an approval rating above 40 percent, compared with only 27 percent for the tax cut.

Trump’s popularity among Republicans probably helps explain why poll respondents from both parties were pretty lukewarm about the prospect of impeachment proceedings. Only 30 percent of Democrats thought Congress should start the impeachment now, with most preferring to see more investigation into the Trump campaign’s involvement with the Russians. The new poll suggests that public opinion on the Russia question isn’t likely to change much going forward, even if Mueller himself finally does speak publicly about his investigation. A member of the House Judiciary Committee announced Sunday that Mueller has been invited to appear before it on May 15, but so far the date hasn’t been confirmed.

Trump, for his part, sees no need for Mueller to testify: