Donald Trump won a second term as president on Wednesday after scoring victories in key battleground states, NBC News predicts. Democrats are wondering what went wrong.

The historic victory was revenge for Trump's loss in the 2020 election, which he and many of his supporters baselessly claimed was stolen from him.

“I think we just experienced the greatest political comeback in the history of the United States of America,” Sen. JD Vance, R-Ohio, Trump's vice presidential running mate, said early Wednesday at the campaign victory party in West Palm Beach, Florida.

Trump and Vance spoke before most news outlets had declared him the winner, but the evening was clearly going his way at that point. Trump thanked his supporters for the “extraordinary honor of being elected your 47th president and your 45th president.”

Democrats were stunned as one battleground state after another flipped to Republicans. One veteran Democratic strategist said of the party's poor reputation: “Have you ever been to a funeral? That would be a carnival compared to that.”

The defeat leaves the Democratic Party without a clear leader and searching for answers about how Trump became the first Republican in 20 years to win the popular vote.

“How is it possible that we lose to this guy? It’s simply misconduct,” a Democratic fundraiser said.

Vice President Kamala Harris skipped an election night address to her supporters in Washington, D.C., after Trump won Georgia and North Carolina, the first two battlegrounds to fall in the race for the White House.

Cedric Richmond, co-chairman of Harris' campaign, told the crowd at Howard University that she would not speak publicly until later Wednesday.

“We still have to count votes. We still have states that haven’t been called,” Richmond said just before 1 a.m. ET. “You’ll hear from her tomorrow.”

The decision to remain silent coincided with a dramatic shift in sentiment among her campaign aides, supporters and Democratic officials as vote totals in battleground states suggested the path to victory was narrowing.

At Harris headquarters on the Howard campus, thousands stared at the screens in near silence and appeared stone-faced. No one waved the American flags that were distributed earlier in the evening. The mood changed from joyful and celebratory to worried and fearful.

A few dozen people in the crowd, visibly finished looking at the returns, began chanting, “Music! Music!” Moments later, a giant screen showing cable news muted and the DJ began playing rap music. Some of Harris' staffers paced back and forth with blank expressions on their faces.

It is an ominous development for Democrats that the share of voters who identify with their party has reached its lowest point this century. According to the NBC News Exit Poll, 32% of voters identified as Democrats, compared to 37% four years ago. The poll also found that most voters this century identify as independent or “something else” (34%). The share of voters who identify as Republican has changed less, standing at 34% this year.

Supporters of the two candidates were divided over the main issues facing the country on election day. These disagreements partly reflected what they focused on. NBC News exit polls also showed significant demographic changes in the two parties' coalitions.

Among the most significant changes: Latino men favored Trump by a 10-point margin, 54% to 44%, after supporting 2020 Democratic nominee Joe Biden by a 23-point margin, 59% to 36%.

In a smaller shift — but a sizable one in its own right — Harris had a 25-point lead among Latino women, 14 points shy of Biden's 39-point lead over Trump in 2020.

At the same time, Trump experienced a decline among suburban white women, with exit polls showing 51% of them this year compared to 56% four years ago. Harris also received a boost from older voters, with the over-65 group rising from 50% to 49%. That wiped out Trump's 5-point victory in 2020 among seniors. Additionally, older voters made up 28% of the electorate, up from 22% in 2020.

Most Harris voters rated democracy as their most important issue, while most Trump voters said the economy was most important to them. Overall, 35% of voters named democracy at the top of their list, while 31% named the economy and 14% named abortion.

Fifty-six percent of Harris voters put democracy first, while 21 percent named abortion as their top priority and 13 percent chose the economy. 51 percent of Trump voters saw the economy as the biggest problem, 20 percent said immigration and 12 percent said democracy.

Harris promised that she would restore abortion rights, which were restricted by the Supreme Court's Dobbs decision. Trump said abortion decisions fall into the hands of the states where they now lie, but he supports bans that exempt cases of rape, incest and danger to the woman's life.

Overall, 51% of voters in 2020 said abortion should be legal in all or most cases. But now 66% say that. At the same time, the share of voters who believe abortion should be illegal in all cases has fallen from 17% in 2020 to 6% this year.

Both candidates and their campaigns have expressed confidence in recent days that they are on the path to victory.

“The momentum is on our side,” Harris said Monday night at her latest rally in Philadelphia.

“I think we're going to have a very big victory today,” Trump said as he cast his vote in West Palm Beach on Tuesday afternoon.

Despite the candidates' success, 72% of voters in NBC News polls said they were either angry or dissatisfied with the state of the country, while just 26% said they were satisfied or thrilled with it.

There were signs of demographic changes in the electorate in early election polls. Trump's popularity declined among white voters while it increased among black and Latino voters. In 2020, 57% of white voters viewed Trump favorably, as did 38% of Latino voters and 10% of Black voters. This year, just 49% of white voters said they view Trump favorably, while his numbers among Latino and black voters rose to 42% and 14%, respectively.