House Minority Leader Nancy Pelosi, D-Calif., seems to have no doubts that Democrats will win big in the upcoming midterm elections, despite recent warnings the party may be overconfident. The only question for Pelosi is how big.

“People ask me all over the country, ‘Is it a wave, or is it a tsunami?'” Pelosi said Tuesday during a speech at the John F. Kennedy School of Government at Harvard University. “And I said, well, in either case, it’s little drops of water. And many of them. How many a wave, how many more a tsunami. But they’re all close. They’re all very, very close. These are many close races.

“I think if the election were today, we would win the majority. I don’t know how much water would be involved, but we would win the majority. Wave or tsunami, we’ll see in three weeks.”

Pelosi added that she believes the momentum in the run-up to the midterms is with the Democrats and she has “never seen anything like” the party’s current get-out-the-vote push

“I would much rather, from the standpoint of handicapping, be Democrats than Republicans today,” she said. “We’re in a much better place. Voting is beginning, and so we intend — we have fabulous candidates on the field.”

She added: “I’ve never seen anything like it, the mobilization that is out there.”

I think if the election were today, we would win the majority. I don’t know how much water would be involved, but we would win the majority. Wave or tsunami, we’ll see in three weeks. — House Minority Leader Nancy Pelosi, D-Calif.

Pelosi’s public confidence, however, is not shared by all Democratic insiders who are still stinging from President Trump’s upset victory Hillary Clinton in the 2016 election.

“Election Day will either prove to me I have PTSD or show I’ve been living déjà vu,” former Clinton spokesman Jesse Ferguson told McClatchy about the upcoming elections. “I just don’t know which yet.”

Al Sharpton, the liberal cable news host who ran for president as a Democrat in 2004, said Democrats shouldn’t take anything “for granted” ahead of next month's vote, citing what happened in 2016.

“I think that if they just look at the polls and relax, they will end up having the same result they had in '16 when every Democrat I know were already planning what they were wearing to Hillary Clinton's inauguration and we never got there,” Sharpton said last week on MSNBC.

Democrats are still widely favored to win the House. But on the Senate side, Republicans – emboldened by the confirmation to the Supreme Court of Brett Kavanaugh – appear reinvigorated to not only to hold onto their slim majority in the Senate but potentially expand it.

The GOP's chances of flipping key seats currently held by Democrats in Trump-won territory seem to be improving -- especially in North Dakota, where incumbent Democratic Sen. Heidi Heitkamp is slipping further behind GOP challenger Kevin Cramer.

Republicans are also strengthening their position to hold seats that Democrats are fighting to flip. Analysts are warning that Democrats, who extensively focused in recent months on longshot bids to derail Republican candidates in reliably red states, may have neglected critical Midwest battleground states in a miscalculation reminiscent of the 2016 presidential election.

Fox News Alex Pappas and Gregg Re contributed to this report.