"Elections have ramifications, and here is a living, breathing example of it," Pelosi said Tuesday night during a CNN town hall moderated by Jake Tapper.
Pelosi cited Gorsuch's rulings on health care, gun safety and environmental issues to explain her concerns. She said Senate Democrats -- who only have 48 seats and have not yet determined whether to attempt to block Gorsuch's nomination -- should apply the "strongest scrutiny."
But Pelosi did not say whether Democrats should filibuster Gorsuch, a move some in the party would rather use for a future nominee who could change the court's balance of power.
Pelosi was speaker from 2007 until the GOP took the House majority in the 2010 wave. She is still the most powerful House Democrat, having staved off a challenge for her leadership post by Ohio Rep. Tim Ryan.
As progressive anger with Trump spills over, Pelosi and other top lawmakers are attempting to channel the resistance into legislative victories. Out of power and without the same procedural tools that Senate Democrats have to block Trump's actions, House Democrats' strength comes mostly from uniting in opposition to the GOP.
'Sorry' for Trump
Pelosi said she feels "sorry" for Trump because he believes -- as he told her and other congressional leaders in a recent meeting -- that 3 to 5 million people voted illegally in the 2016 election. There's no evidence to back up that claim.
"When I said, 'that's not true, there's no evidence to support that," Pelosi said, "he said, 'and I'm not even counting California.'"
"You know what it is? It's a predicate for the President to go out and say, there's voter fraud rampant around the country," she said. "And it's not true."
Pelosi criticized Republican lawmakers for moves to restrict access to abortions -- and told a questioner that lawmakers should increase access to family planning, birth control and contraception and not "defund Planned Parenthood."
When an anti-abortion college student who said her mother chose to give her up for adoption challenged Pelosi, she responded: "You said, my mother chose -- my mother chose. And we want ... people to have that opportunity to choose, as well."
Pelosi lashed out at Trump over his executive order banning travel to the United States from seven majority Muslim countries -- calling it a "decoy, decoy, decoy, decoy."
"Our president is reckless -- reckless and his administration is incompetent," she said. "How and why they did this is because they are grand illusionists. Anytime they have a problem with something, they create another problem."
A Texas veterinarian who described struggles with violence among smugglers at the border asked Pelosi if she would support Trump's calls for a border wall and to eliminate sanctuary cities.
"A lot of the thinking is, we need more technology, more manpower, some fencing, perhaps," Pelosi said.
She added: "With more technology and more manpower I think we have a better result than thinking that Mexico is going to pay $10 to $20 billion to build a wall."
Pelosi defended so-called sanctuary cities -- which do not deport undocumented immigrants -- arguing that they make the United States safer by bringing those immigrants into full society.
Laura Wilkerson, who said her son was tied up and slain by an undocumented immigrant, pressed Pelosi on her support for sanctuary cities with an emotional question.
Pelosi said she "prayed" for the woman and said her son's killer "should be deported" or "sent to jail."
But Pelosi also defended law-abiding undocumented immigrants in sanctuary cities.
"The point is that you do not turn law enforcement officers into immigration officers. That is really what the point is in sanctuary cities," she said.
'Run for office'
Pelosi also confronted Democrats' failings in the 2016 campaign.
She admitted to a steel manufacturer that Democrats have fretted internally about how they managed to lose blue-collar workers in the Midwest.
"In our caucus, we've had this discussion: 'How did they not know we're there for him?'" she said.
"It's not about who we are, because who we are is to be there for America's workers, and we fight that fight every day," Pelosi said.
Pelosi told a female college student who had participated in the Women's march in Washington -- but was frustrated it didn't catch Trump's attention -- to get directly involved in the political process.
"You've marched for progress -- now run for office," she said. "Run for office. We need many more women to run for office."