A growing number of House Democrats are eager to start impeachment proceedings against President Trump as his White House rebuffs cooperation with multiple congressional investigations into his finances, his businesses and his administration.

The dozens of impeachment supporters are still vastly outnumbered by Democrats who view the tactic as politically toxic and liable to backfire in 2020. Speaker Nancy Pelosi argues there is not enough bipartisan support or overwhelming evidence of wrongdoing, even though she says Trump is engaging in a “coverup.”

Impeachment — which Trump called a “dirty, filthy, disgusting word” on Thursday — will hang in the air next week when lawmakers return to Washington to consider whether to hold members of his administration in contempt of Congress.

Here’s how the impeachment process would work:

Typically, impeachment begins with a vote by the House of Representatives to instruct the Judiciary Committee to determine whether there are sufficient grounds for Congress to impeach the president. The Constitution provides Congress only vague guidance, saying impeachment is warranted for “treason, bribery, or other high crimes and misdemeanors."

The inquiry likely would consist of public hearings with experts and requests to the Trump administration for more information. Later, the committee could write up articles of impeachment and vote on whether to send it to the full House for consideration.

No. An inquiry is merely an investigation that could lead to articles of impeachment brought before the House. It may end with a decision not to pursue impeachment.

But that seems unlikely. Senior House Democrats who are skeptical of rushing toward impeachment — including Pelosi — suggest it would be hard to slow the political momentum toward impeachment if an inquiry were to began. And much of the public may not draw a distinction between an impeachment inquiry and impeachment.

“We haven’t done a very good job of explaining that, when we use the word ‘impeachment,’ it starts with a process that may not even produce an impeachment vote,” said Rep. Jared Huffman (D-San Rafael), who supports an inquiry.

Maybe. Advocates of an impeachment inquiry say federal courts — where several of Congress’ investigations have detoured or may end up — are more likely to uphold the legislative branch’s subpoena power if it is part of an impeachment inquiry.

Michael Conway, who was on staff with the House Judiciary Committee when it conducted impeachment proceedings against President Nixon during Watergate, argues that Congress’ power reaches its peak during an impeachment.

“Only by instituting an impeachment proceeding will Congress be equipped to act on the evidence that Mueller intended to convey to it,” he wrote in an opinion piece for NBC.

Rep. Jerrold Nadler (D-N.Y.), who heads the House Judiciary Committee, has suggested that an inquiry could help the committee get additional information, such as access to the grand jury testimony included in the Mueller report but redacted by the Justice Department.

But federal courts already have delivered House Democrats two legal victories, upholding Congress’ power to subpoena Trump’s accountant, Mazars USA, as well as his banks, Deutsche Bank AG and Capital One Financial. Trump is appealing both rulings.

Nadler and the leaders of other committees “have had the authority to pursue these issues without calling it an impeachment process,” said Steven S. Smith, an expert on congressional procedure at Washington University in St. Louis. “Merely labeling it an impeachment inquiry doesn’t change much.”

Plus, some lawmakers worry about setting a bad precedent for Congress’ power to conduct oversight.

“I am concerned about setting the precedent that the only way apparently a future Congress can investigate an administration is by launching a technical, formal impeachment inquiry,” said Rep. Gerry Connolly (D-Va.). “I do not agree with that.”

Right now, no. Dozens of the 235 House Democrats don’t support impeachment, arguing that the Constitution’s bar of “high crimes and misdemeanors” has not been met, or that they want to let other investigations play out. Some believe Trump is goading the impeachment effort to rally his supporters in the 2020 race.

But two recent incidents prompted more Democrats to support an impeachment inquiry: Former White House Counsel Donald McGahn’s refusal to appear at a House Judiciary hearing despite a subpoena, and special counsel Robert S. Mueller III’s public refusal to clear Trump of a crime.

Rep. David Cicilline (D-R.I.), one of the few members of the House Democratic leadership to come out in favor of an inquiry, said he expected support to grow with time. Trump’s behavior will “continue to have an effect on the attitude of the American people about impeachment,” he said, and will “continue to have an effect on members of our caucus.”

Yes. Any member of the House can bring an impeachment resolution. Because of special rules around impeachment, he or she could force a vote on the House floor within two days.

Rep. Al Green (D-Texas) has already forced the House to vote two times on whether to bring articles of impeachment against Trump, but he did so when Republicans were in charge of the House. Now that Democrats are in power, a similar measure would carry starker political consequences for rank-and-file Democrats who have mixed feelings about impeachment.

Earlier this year, Green said he would bring his resolution up again if leadership did not do so, but he has not indicated when that might happen.

No president has been removed from office by Congress. But the threat of removal forced President Nixon to resign in 1974. And two presidents — Bill Clinton in 1998 and Andrew Johnson in 1868 — were impeached by the House but not convicted by the Senate.

In its history, the House has impeached only 17 other people: 15 federal judges, one senator and one Cabinet member. Only eight — all federal judges — were convicted by the Senate and removed from office.