Kamala Harris at the Georgia State Convention Center: The First Black and South Asian Presidential Candidate since the 2008 Presidential Indictment Campaign

The crowd that cut across generations in the belly of the Georgia State Convocation Center Tuesday night were electric over the prospect of a Kamala Harris presidency, or perhaps dead set on wanting to ward off another Trump White House. There was no mistaking the pandemonium. In the same state where Donald Trump was indicted on election interference charges, Vice President Harris drew her biggest crowd of supporters. Kamalamania had arrived.

There was star power in every direction. Rapper Quavo underscored the importance of voting. Megan Thee Stallion twerked to “Savage.” The senator spoke of “an America that embraces all of our children.” The night began with Georgia’s rising political star, which reinforced Harris’ moral imperative for the country. Before long, chants of “Not going back” filled the arena.

It was an unlikely sight. But these are unlikely times. If Harris is elected, she will be the first black and South Asian president in the history of the country, which has never had a woman hold the office.

The support of Black voters will be required to get to there, but they have loosened a bit in the last few years. According to one Pew study, 85 percent of Black voters with college degrees identified with the Democratic Party in 2020. By 2023, that number dropped to 79 percent. Data for Progress said the party will likely cede ground to the Black voter this year as a result of the President Barack Obama election in 2008.

Tuesday was a test of Harris national appeal. It included all the ornamentation of a rock concert and perhaps for the first time since the 2008 campaign, Democrats were again aware of the importance of what it called for. She wasted no time when the vice president took the stage. She admitted that she was familiar with Donald Trump’s criminal past.

It was also true that the rally was a portrait of a multicultural America as much as it was calculated political theater—the very scene that inspires voters to show up on Election Day, but one that also gets called out for its over-the-top fanaticism.

They were not completely off the mark. Since Harris entered the race less than two weeks ago, she has undergone a remarkable catapult into popular culture. Every identity group started grassroots organizing. Informal rallies were held. Record amounts of cash poured in. The campaign surpassed $200 million in donations in a week, much of it from first-time supporters. Harris had also done the impossible, by knocking Donald Trump out of the news cycle, reorienting the media’s center of gravity, and embracing the meme of brat summer.

Ms. Harris will not be able to win the presidency in Electoral College swing states unless she can convince voters of the kind of centrist policies that were essential to the victories of Mr. Biden, Obama and Clinton. Pick Gov. Josh Shapiro of Pennsylvania as her running mate would be an emphatic and persuasive remedy to that problem.

Mr. Shapiro would make sure to assure Jewish voters that there was nothing hostile happening in the party, even at a time when many of them have seen antisemitism coming from some of the far left. Now, some pundits and analysts of presidents and their running mates will wonder if adding an observant Jew to a ticket headed by a Black woman is a ticket to nowhere. The elections of Mr. Obama suggest that America is focused on party unity and preventing Donald Trump than on race and religion. Remember that Joe Lieberman was the first Jewish vice-presidential nominee, in 2000, and he deepened the heft, experience and integrity of the ticket led by Al Gore.

Vice President Kamala Harris is perceived to be to the left of Joe Biden as a candidate for president. Ms. Harris supports single-payer health care, is against Immigration and Customs Enforcement, and supported the defund the police movement. Her opponents have blamed her for what they see as a too-porous southern border.