Hours before the expected House vote on two articles of impeachment against President Donald Trump, hundreds of thousands of people poured into the streets across the United States Tuesday night to show Congress that there is a "nationwide movement" behind the effort to hold the president accountable by removing him from office.

At more than 600 locations across the country, from Arkansas to Colorado to New York, massive crowds gathered to demand that Trump be impeached and removed for abusing the power of the presidency and other offenses.

"Trump did it. He admitted to it. The House confirmed it. And now he'll be impeached for it," Ezra Levin, co-executive director of Indivisible, said in a statement late Tuesday. "After tomorrow's House vote, Indivisible will focus our grassroots power on ensuring Trump's Senate allies don't get away with a sham trial and conspiratorial cover-up."

MoveOn, which joined Indivisible and other advocacy groups in organizing the demonstrations, tweeted that "across the nation tonight, hundreds of thousands said with one voice that it's time to impeach and remove Trump."

According to an analysis by the Washington Post, the Democrat-controlled House has enough votes to approve the articles of impeachment against Trump without any Republican support.

"Trump will be impeached if the House passes one or both articles by a simple majority (That means House Democrats need 216 votes given the current makeup of the House—there are a handful of vacant seats)," the Post reported Tuesday night. "A majority of House lawmakers have indicated their support for both articles of impeachment."

Ahead of his likely impeachment, Trump on Tuesday lashed out at House Speaker Nancy Pelosi (D-Calif.) in a letter critics described as "unhinged" and "deranged."

"It could not be more clear that Trump is a clear and present danger to our democracy—and that he must be impeached and removed," Sean Eldridge, founder of advocacy group Stand Up America, said in a statement. "That's why hundreds of thousands of Americans are taking to the streets... to demand Congress remove him from office."