On Jan. 20, the country will witness something that has never happened: A woman — the mixed-race daughter of immigrants from India and Jamaica — will raise her right hand and be sworn in as vice president of the United States.

History will have been made. What remains to be seen is precisely what kind of governing partner Kamala D. Harris will be for incoming president Joe Biden, and whether she will experience the frustrations that so many of her male predecessors have found in the job. While it has never been definitively proved that Franklin D. Roosevelt’s vice president John Nance Garner called the role “not worth a bucket of warm spit,” that was a sentiment that more than a few before him and since have shared.

Harris, who carries the hopes of women and non-White Americans thrilled by her ascension and by the life experiences she will bring to the table, will face a delicate set of challenges. For starters, Biden has not discouraged the assumption that he will serve only one term. So from her first day in office, Harris will be measured as a potential president-in-waiting.

Advisers have told me that among her imperatives will be a need to build out her résumé beyond the areas that she dealt with most closely as a U.S. senator from California, such as criminal justice. As vice president, she will have the opportunity to deepen her grounding on foreign policy and economic issues.

But having a vice president who is assumed to aspire to run for the top job also creates a different dynamic — and potential tension — within the White House.

One thing that could work in her favor: Biden’s incoming chief of staff, Ronald A. Klain, knows well how to manage this, having served as the top aide to two previous vice presidents, Al Gore and Biden himself.

Her recent vice-presidential predecessors, notably Biden himself, have generally been Washington veterans who have arrived with their own cadres of long-serving aides. Harris will have a team largely composed of people who are relatively new to her orbit. Her allies were heartened when she picked as her own chief of staff Tina Flournoy, a well-connected and seasoned hand with decades of Washington experience.

But there is also the question of how Harris and Biden will define the job of vice president itself. Modern vice presidents have generally followed one of two models.

The first sees the vice president taking charge of specific policy areas, as Gore did under Bill Clinton to become the administration’s leading voice on the environment and to steer its government-reorganization initiative.

During George W. Bush’s administration, his vice president, Richard B. Cheney — widely regarded as the most influential in history to hold the post — became a power center unto himself, steering policy on matters that ranged from national security to budget priorities to the environment.

But Biden says he prefers the approach that he himself took during the eight years he was vice president under Barack Obama. He began with no defined portfolio, although the two of them agreed that he would be the first and last person the president talked to before making any major decision.

Beyond that, Obama also turned to Biden as a sort of fireman to handle urgent challenges.

One came early in his presidency, in February 2009, when Obama tapped his vice president to oversee the implementation of the contentious American Recovery and Reinvestment Act, which was the $787 billion economic stimulus package Congress passed to deal with the brutal recession that had been caused by a collapse of the financial system.

An early indicator of Harris’s influence will be whether she takes a leadership role on Biden’s first order of business: dealing with the covid-19 pandemic.

Transition aides note that Harris has already shown a desire to become involved in some of the ground-level issues that have arisen. During her final months as a senator from California, Harris has introduced legislation that would provide grants of up to $250,000 to struggling small businesses, such as barber shops, hair salons, food trucks and neighborhood bodegas.

With data showing the virus having the most devastating effects on minority communities, she also wrote a bill aimed at assuring that racial disparities are accurately measured and taken into account in allocating federal funds and other resources against covid-19.

In a joint interview that she and Biden did with CNN’s Jake Tapper last week, Harris defined her role this way: “On every issue that impacts the American people, I will be a full partner to the president-elect and the president. And whatever our priorities are, I will be there to support him and support the American people.”

That is a broad canvas, one on which we will soon get to see how Harris makes her mark.

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