A protester holds up a sign during a demonstration calling for members of Congress to begin the impeachment process at the U.S. Capitol in Washington, September 26, 2019.

The apparent shift in sentiment on impeachment comes as Democrats try to limit potential 2020 electoral backlash from moving forward with proceedings. Pelosi had called impeachment "divisive" until support for an inquiry swelled within her caucus. Meanwhile, Trump allies contend the proceedings could help the president and Republicans running against pro-impeachment Democrats in swing districts.

Public support for an impeachment inquiry into President Donald Trump jumped in the days after Democrats announced a probe of his conduct.

Here are results from a few of the surveys on impeachment taken after Pelosi announced on Tuesday that the House would start an inquiry:

A Quinnipiac University survey found 47% of registered voters think Trump should be impeached and removed from office, while the same share of voters think he should not. Support for impeaching Trump jumped 10 percentage points from a Quinnipiac poll released only last week. The rise was most pronounced among Democrats: 90% of those voters said they backed impeaching Trump, up from 73% in the previous poll. Meanwhile, 52% of voters said they approve of the House's impeachment inquiry, while 45% disapprove. The survey, taken from Friday to Sunday, has a margin of error of plus-or-minus 3.6 percentage points.

A CBS News/YouGov poll found 55% of Americans approve of Democrats starting an impeachment inquiry, versus 45% who disapprove. The survey found nearly 90% of Democrats back an inquiry, while 49% of independents and only 23% of Republicans support one. The poll was taken Thursday and Friday and has a margin of error of plus-or-minus 2.3 percentage points.

A Politico/Morning Consult poll showed 43% of voters think Congress should start an impeachment inquiry into Trump. The same share of voters said lawmakers should not go forward with proceedings. The survey was taken Tuesday through Thursday. Support for impeachment jumped 7 percentage points from a previous poll taken Sept. 20-22.

A Hill-HarrisX poll found 47% of registered voters back Democrats' decision to start an impeachment inquiry, while 42% oppose the move. Support for impeachment spiked 12 percentage points from three months ago. The survey was taken Thursday and Friday and has a margin of error of plus-or-minus 3.1 percentage points.

As they start the probe, Democrats are trying to balance a desire to show they are taking their time to find facts with a reluctance to let an impeachment inquiry drag on for too long. It is unclear whether longer proceedings would help the president politically.

Impeachment supporters have argued Trump abused his power and compromised national security by urging Ukrainian President Volodymyr Zelensky to investigate Hunter Biden, the former vice president's son who sat on the board of a Ukrainian energy company. A whistleblower complaint at the center of the inquiry raises concerns about the president abusing his power to encourage foreign interference in the 2020 election.

The whistleblower also outlines Trump administration efforts to "lock down" records of Trump's July call with Zelensky. Facing pressure as support for impeachment mounted last week, the administration released both a summary of the call and a redacted version of the whistleblower complaint.

Meanwhile, Democrats have raised questions about whether Trump's push to investigate the Bidens relates to his decision earlier this year to temporarily withhold nearly $400 million in military aid to Ukraine.

Trump has lashed out as the scrutiny of his conduct increases, calling the impeachment probe a Democratic effort to discredit the work he has done in office. The president tweeted on Monday that the probe is "The Greatest Witch Hunt in the history of our Country!"

In a statement, Trump campaign spokeswoman Kayleigh McEnany called the probe "yet another attempt by Democrats to disenfranchise the American people by removing a duly elected President that they disdain."

"President Trump has done nothing wrong, and the transcript fully and completely exonerates him. Despite the obstructionist Democrats, President Trump will continue to win for the American people with a historic economy, lowered prescription drug costs, a secure border, new and better trade deals, and leadership on the world stage," she said.

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