Democrats would likely launch investigations into the various controversies surrounding Trump if they won control of the House.
"This online community is bigger than the NRA," Need to Impeach founder Tom Steyer said.
It is unclear whether Trump saw the lettering.
"If there is conclusory evidence that shows unequivocally that he lied to a Senate committee, that is a crime and he should be held accountable," the New Jersey senator said.
The campaign circulated a second petition against Kavanaugh's confirmation that has received more than 297,000 signatures.
"These are the kinds of things that can cause long-term harm to society," Green said.
"The cover-up is always worse than the crime, and this one is very shady," the Watergate lawyer said.
Among poll participants, 49 percent thought Congress should begin impeachment proceedings against Trump, while 36 percent approved of his job performance.
"I don't think they can impeach somebody that's doing a great job," Trump said.
"You could only impeach him for political reasons and the American people would revolt against that," Giuliani claimed of Trump.
"Such a time is upon us," Democratic Representative Al Green stated.
"President Donald Trump has been violating the Constitution since the moment he took the oath of office," the book states.
"Those who don't act should be tossed Nov. 6," documentary filmmaker Michael Moore tweeted Tuesday.
"Impeach him for what? No," Gowdy told CBS News.
"If Paul Revere and other patriots had waited to act until it was safe or politically correct, we would never have the country we have today," Steyer says in the ad.
"Impeachment of the president would be the better answer" over criminal prosecution, Lanny Davis opined.
"My question is, why hasn't Congress started impeachment proceedings given what we know, and they probably know more," a Denver resident said in an ad.
A Democratic congressman in Texas who has repeatedly called for President Donald Trump's impeachment said Tuesday that every House representative has a "right and privilege" to bring up impeaching Trump.
The Trump impeachment guide contains "steps we must take to remove one of the gravest dangers our country has ever confronted."
The California representative said that Martin Luther King Jr. would work to impeach President Trump.
The Democrats' efforts to open impeachment hearings in the House have failed so far.
Jerrold Nadler could lead the initial charge in impeachment proceedings before a vote on House floor.