The White House did not respond to a question about which poll the president was citing, and Trump did not specify what category of people was purportedly surveyed.
Trump cited the same figure later Monday during a wide-ranging speech to a gathering of conservative students in Washington but did not elaborate.
Recent polls have found that impeachment is not a particularly popular option among Americans at this point, but support is higher in recent polls than the figure Trump cited.
A Washington Post-ABC News poll published this month found that 37 percent of adults supported beginning impeachment proceedings, while 59 percent opposed the move.
In an NBC News-Wall Street Journal poll published this week, support among registered voters for launching impeachment proceedings was lower than in the Post-ABC poll, at 21 percent. But that poll also offered a choice of continuing to investigate Trump that was supported by an additional 27 percent of registered voters. Fifty percent said Congress should not hold hearings.
Meanwhile, an Economist-YouGov poll this month found that 36 percent of adults support efforts in the House to impeach Trump, while 45 percent were opposed.
In that poll, 11 percent of Republicans supported efforts to impeach Trump. It’s possible that that is the figure Trump was referencing in his tweet, but the poll was conducted more than a week ago and would not be the “newest.”
Trump’s tweets came on the eve of highly anticipated congressional testimony from former special counsel Robert S. Mueller III about his report on Russian interference in the 2016 presidential election. Pro-impeachment Democrats hope that Mueller’s appearance will help build support for a case that Trump obstructed the special counsel’s probe.
More than 90 House Democrats have called for launching impeachment proceedings, but House Speaker Nancy Pelosi (D-Calif.) has resisted the idea.
“These people have gone totally crazy,” Trump said during his remarks to the gathering of students sponsored by Turning Point USA, referring to lawmakers who have called for his impeachment.
Trump also criticized Congress again for following up on the Mueller probe.
“How about this whole witch hunt that’s going on?” he asked the students. “It makes it very hard to deal with Russia.”
Emily Guskin contributed to this report.