Sen. Kamala Harris (D-Calif.) is moving front and center in the presidential campaign, seeking to build on the momentum from her selection as Joe Biden’s running mate last month.

The Democratic vice presidential nominee made her first in-person appearance on the campaign trail in Wisconsin on Monday, and appeared in an online video with former President Obama Tuesday morning.

She will campaign in Miami on Thursday amid polling showing a tightening race in Florida, the largest battleground state.

Harris, whose own bid for the Democratic presidential nomination fizzled despite early high expectations, has injected some excitement into a campaign that has been constrained by precautions around the coronavirus.

“She is helping to energize the base of the Democratic Party as well as helping with outreach to younger voters and women,” said Karen Finney, a Democratic strategist who was senior spokesperson for Hillary Clinton’s 2016 presidential campaign. “She is doing what you expect from a vice president — to deepen support and broaden support.”

Harris also brings some sense of newness to the ticket headed by Biden, 77, who was first elected to the U.S. Senate in 1972. Harris, 55, is in her first Senate term.

Harris’s comparative youth is already producing some viral moments. The Washington Post reported on Tuesday afternoon that brief video snippets of her arrival in Wisconsin the previous day, posted on Twitter by two reporters, had been viewed almost 8 million times by the following morning.

“What sent video pinging around the internet was what was on her feet: her black, low-rise Chuck Taylor All-Stars, the classic shoe that has long been associated more closely with cultural cool than carefully managed high-profile candidacies,” the Post reported.

But if things have gone smoothly for Harris so far, that doesn’t mean it will be all plain sailing. President Trump’s campaign is grappling with ways to erode Harris’s image.

Trump contended during a Tuesday evening rally in Winston-Salem, N.C., that Harris ever becoming president would be "an insult to our country." At the same event, he pronounced her first name in a mocking tone several times and insisted "Nobody likes her."

A Politico report on Sunday outlined broader Trump campaign plans to tag Harris as a “California liberal” and to try to exploit differences of opinion between her and Biden on major issues such as health care and abortion.

Polling so far suggests Harris is fairly popular — but that polling is also sparse and not especially consistent.

Two major polls conducted at the same time last month — Aug. 12-15 — both found Harris to be viewed favorably by the general public. But one, from ABC News and The Washington Post, found an outright majority, 52 percent, of adults holding a favorable view of her, while the other, from CNN, found only 41 percent who did so.

Part of the disparity lay in the CNN poll finding that more than 1 in 5 respondents either had no opinion about Harris or claimed to have never heard of her.

Democrats are largely enthused by Harris’s performance so far, viewing her as someone who can boost Biden without eclipsing him.

Democratic strategist Joel Payne said that she brings “diversity, energy and an ability to serve as a generational connector of sorts” to the ticket. “Obviously, the lazy comparison is the age difference [between Harris and Biden] but it is really about who can connect to a younger, more millennial Democrat — and Kamala Harris can do that.”

Harris is already a historical figure, by virtue of simply being tapped as Biden’s running mate.

She is the first woman of color on a major party’s presidential ticket, and only the fourth woman in history in that role: Democrat Geraldine Ferraro in 1984 and Republican Sarah Palin in 2008 were vice presidential candidates, before Hillary Clinton became the first female presidential nominee of a major party in 2016.

The historic nature of Harris’s candidacy has contributed to the fundraising boost that Democrats have enjoyed recently. The Biden campaign and the Democratic National Committee raised an eye-popping $364.5 million in August. Harris was announced as Biden’s running mate on Aug. 11.

Some Democrats behind the scenes raise the delicate question of whether Harris could overshadow Biden, who has been a familiar figure to American voters for a generation.

During Biden’s vice presidential search, there was some whispering about whether Harris was too ambitious or self-promoting — a critique that received its own blowback from those who argued that the same terminology is rarely used about male candidates.

Harris has played a staunchly supportive role so far and some experts say the idea of a vice presidential candidate overshadowing her or his running mate is exaggerated.

Joel Goldstein, a professor emeritus at Saint Louis University and an expert on the vice presidency, said Harris’s barrier-breaking potential would mean that “the election of Sen. Harris would in a sense be more historic than the election of whoever is elected president.”

“But,” he added, “I think it is impossible for a vice presidential candidate or vice president to overshadow a president, because of the disparity of power. … How important a vice president is going to be is derivative of his or her relationship with the president.”

The Memo is a reported column by Niall Stanage, primarily focused on Donald Trump’s presidency.