Vice President Harris is opening a sizable lead over President Trump with a critical demographic that will help decide the presidential election — voters under 30. This comes even as her boss, President Biden, is suffering some of the worst approval ratings among young voters for a Democratic president in recent memory.

The youth vote was critical to Mr. Biden’s victory in 2020, when he won voters under 30 by a 20-point margin over Trump. Before he dropped out of the race, his margin of support from young voters had winnowed to just single digits, and some polls even found Trump winning the cohort. 

Now, Ms. Harris has retaken that advantage, and then some. According to Harvard University’s youth poll, Ms. Harris leads Trump by 31 points among likely voters between the ages of 18 and 30. She takes 61 percent of the vote compared to Trump’s 30 percent. 

That same group says they are energized and ready to vote in the upcoming election. A majority, 56 percent, say they will “definitely” cast ballots this year, and 13 percent say they “probably” will. 

The momentum for Ms. Harris is based less on love of her and her policies than it is for keeping Trump out of the White House again. A majority of young voters who support the Democratic ticket say denying Trump a second term is what is motivating them this year. For those young voters who support Trump, 72 percent say they are voting for him because of his policy positions. 

“In just a few weeks, Vice President Harris has drummed up a wave of enthusiasm among young voters,” the chair of the Harvard Public Opinion Project, Anil Cacodcar, told The Hill. “Harris is enjoying a perfect storm of personal appeal, policy support, and positive reach on social media.”

While Ms. Harris is viewed as more competent to handle issues like climate change, the Ukraine war, gun violence, and crime, Trump is still winning on critical issues that voters say will determine their candidate choice in November. Among voters under 30, Trump is more trusted to handle the economy, the Israel-Hamas war, immigration, and national security. 

Ms. Harris and her running mate, Governor Walz, are both viewed more positively on a personal level than the Republican ticket this year. Ms. Harris has a 47 percent favorable rating and a 42 percent unfavorable rating, while Mr. Walz holds a 36 percent approval rating and a 22 percent disapproval rating. 

Trump and Senator Vance are seen in an overwhelmingly negative way. The former president is viewed positively by just 31 percent of young voters, compared to 61 percent who view him unfavorably. Of all four major party candidates this year, Mr. Vance has the lowest favorable rating, with just 18 percent having a positive view of him compared to 46 percent who hold an unfavorable view. 

Mr. Biden, too, is deeply unpopular with young voters — an especially poor mark for a sitting Democratic president. Just 36 percent view him favorably, compared to 55 percent who view him unfavorably.