As lawmakers return to Washington this week, Democrats are being prodded by progressive activists and groups to take aggressive action against the president, but Rep. John Yarmuth, D-Ky., said the votes for impeachment just aren't there.

Judiciary Committee Chairman Jerry Nadler, D-N.Y., surprised political onlookers by recently declaring the House had begun formal impeachment proceedings. He has since made court filings seeking more access to special counsel Robert Mueller’s evidence and witnesses as part of his panel's investigation.

Critics of that course of action, including senior Democrats, are concerned that impeaching Trump will embolden his base ahead of the 2020 elections. Speaker Nancy Pelosi, for instance, stiff-armed the idea by saying last week the "public isn’t there on impeachment."

Asked whether the 235-member Democratic caucus can get to the needed majority, Yarmuth expressed doubts in an interview with the Courier Journal.

"I don't think we do right now," he said. "And I think that is really what is guiding Nancy in remaining reluctant to bring impeachment proceedings because she knows, at least at this point she believes, there's no way we can get 218 votes."

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Under the Constitution, the House would vote on one or more articles of impeachment, and if at least one got a majority vote, the president would be impeached. The proceedings would then move to a trial in the Senate, which could remove Trump by a two-thirds vote.

One hundred and thirty-seven House Democrats have stated publicly they support impeachment or an impeachment inquiry, according to a tally by Politico. The other 98 Democrats remain on the fence, saying they don't support the effort at this time.

Trump has regularly used his Twitter pulpit to call attention to Democratic efforts to boot him from office.

"How do you impeach a president who has won perhaps the greatest election of all time," Trump tweeted in January, "done nothing wrong (no Collusion with Russia, it was the Dems that Colluded), had the most successful first two years of any president, and is the most popular Republican in party history 93%?"

Only two presidents — Andrew Johnson and Bill Clinton — have been impeached, but neither was removed from office. Richard Nixon resigned to avoid being impeached.

Yarmuth said he respects concerns about how this could backfire, but he emphasized that Congress has an obligation to take the extraordinary effort based on Trump's conduct.

"I don't believe there is any chance that we can remove him from office at this point based on what we now know," he said. "But two things are going on among Democrats: responding to constituents saying, 'He's got to go' and secondly the obligation to protect the Constitution, which is first and foremost."

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Yarmuth said the articles of impeachment could include obstruction of justice based on information from the Mueller report, other abuses of power and violations of the emoluments clause.

However, public polling shows most Americans do not side with Democrats taking these steps.

Monmouth University released a survey of 800 U.S. adults in late August that found that — despite Trump's low approval numbers — most Americans do not favor impeaching and removing him from office.

A little more than one-third feel that Trump should be impeached and compelled to leave office, while 59% disagree with such a maneuver, according to the survey, which has a 3.5% margin of error.

The same survey showed Trump's overall job rating hovering at about 40% approval and roughly 53% disapproval.

"Donald Trump is not a popular president by most measures, but the appetite for impeachment remains low," Patrick Murray, director of the Monmouth University Polling Institute, said in the polling memo.

Murray said their polling shows among those who disapprove of Trump, a small segment want him removed from office but feel the political calculus of an impeachment trial would not be a smart move ahead of the 2020 presidential race.

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"They are outnumbered, though, by others who disapprove of Trump and feel that putting his misdeeds on the record is worth the effort, even if the prospect of ousting him is doubtful," he said.

Yarmuth, chairman of the House Budget Committee, has been talking about impeaching Trump since 2017, when he co-sponsored one of five separate articles. He said Pelosi won't bring the issue to the full House floor this fall until there are enough votes, but said it's just as risky for Democrats to take up the idea in the Judiciary Committee.

"It probably would be less embarrassing than if you had a floor vote (that failed), but it would give Trump some talking points for sure," Yarmuth said.

Reach Phillip M. Bailey at pbailey@courier-journal.com or 502-582-4475. Follow him on Twitter at @phillipmbailey.