Harris Created a Huge Wave of Energy. How Long Can Democrats Ride It?

Everything is different now for Democrats.

Their crowds are dancing. Beyoncé has conquered the soundtrack. The celebrities — from Southern rappers to Hollywood actors — are showing up.

And by the time Vice President Kamala Harris took the stage on Tuesday night in Atlanta for what her aides billed as the kickoff for her new-and-improved campaign, it was clear that President Biden had been left a distant memory — a name not even mentioned in her remarks.

“The momentum in this race is shifting,” she declared from behind a lectern embossed with the vice-presidential seal. “There are signs that Donald Trump is feeling it.”

Ms. Harris’s ascent to the top of the ticket has transformed the presidential race into a fundamentally different contest, delivering an electric shock to a listless Democratic Party that for more than a year struggled to mobilize its base behind Mr. Biden.

But the real test awaits: whether Ms. Harris can convert the wave of pent-up liberal energy into sustained momentum. While polling shows that the party’s core voters have rallied behind Ms. Harris, the race remains in a dead heat, reflecting the politics of a fiercely divided nation. After months of Democratic attrition over a weakened candidate, Ms. Harris must now rebuild the coalition that powered Democrats — and the Biden-Harris ticket — to victory in 2020.

In some ways, her campaign remains a work in progress. Though Ms. Harris inherited the 1,300 people working for Mr. Biden’s re-election operation and its $96 million in the bank, her plans to reshape it remain unsettled. She has yet to fully reveal her own vision for the party and the country, beyond what she inherited, or to hold a news media interview.