In May, Sen. Kamala D. Harris (D-Calif.) joined two of the most left-leaning Senate Democrats to introduce legislation that would provide monthly $2,000 payments to tens of millions of Americans throughout the duration of the coronavirus pandemic.

The bill has not advanced or become a major demand of congressional Democratic leaders in their negotiations with the Trump administration over the next stimulus package. But it may gain increased scrutiny in the wake of Tuesday’s announcement that presumptive Democratic presidential nominee Joe Biden has named Harris his running mate.

Biden’s campaign has largely deferred to House Speaker Nancy Pelosi (D-Calif.) and Senate Minority Leader Charles E. Schumer (D-N.Y.) on the specifics of coronavirus stimulus legislation.

Harris has been more aggressive in outlining how the federal government should respond to the economic crisis, introducing both the bill for monthly checks and a proposal to ban evictions, foreclosures, rent increases and utility shutdowns for the duration of the pandemic. Harris’s positions as a U.S. senator and during her 2020 presidential run may pose a challenge for the Biden campaign, which has been wary of moving too far left on economic policy announcements as it tries to maintain its polling lead over President Trump.

“Her positions are, I think it’s fair to say, a few ticks to the left of where Biden has been,” said David Hopkins, a political scientist at Boston College who studies the Democratic Party. “She’s from San Francisco and a California Democrat predisposed to be fairly liberal, and she does not have the long record Biden has of evolving with the party.”

A spokesman for the Biden campaign declined to comment on whether the campaign supports Harris’s effort to provide $2,000 monthly checks throughout the crisis. The spokesman also declined to comment on Harris’s “RELIEF Act,” which in addition to banning evictions and foreclosures would bar landlords from reporting unpaid rent to credit agencies.

Biden’s economic plan for responding to the pandemic says that lawmakers “could include cash payments to working families” as part of a broader package but does not specify an amount for the payment. House Democrats approved a plan in May to send a second round of $1,200 stimulus payments to many Americans, a position Senate Republicans and Trump also support. Democrats’ bill does not require them to be recurring for the duration of the pandemic as in Harris’s plan.

Biden’s plan also pushes a “federal partnership” with states and cities for rental relief “so no one faces evictions,” but not an outright ban. In May, Biden called for the adoption of “rent forgiveness” and “mortgage forgiveness” during the coronavirus crisis.

Jared Bernstein, an outside economic adviser to Biden who served as a top aide during his vice presidency, played down the ideological divergences between the candidates atop the Democratic ticket.

“I viewed the proposal as an aggressive and potentially powerful form of temporary relief to get real money in peoples’ pockets, kind of an amped-up version of the checks that ended up going out," Bernstein said.

A lawyer who served as both district attorney and attorney general, Harris has long been defined in the public eye by her work on criminal justice. Since her election to the Senate in 2016 and as an unsuccessful 2020 presidential candidate, Harris has also unveiled many economic policy measures, including a dramatic tax cut proposal meant to counter the 2017 GOP tax law that she made her signature legislation.

Sen. Kamala D. Harris (D-Calif.) spoke for the first time as presumptive Democratic presidential nominee Joe Biden’s running mate on Aug. 12. (The Washington Post)

That bill — called the LIFT Act — proposed providing $3,000 to individuals (or $6,000 for married couples) earning under $87,000 a year. Almost all of its $2.8 trillion price tag would go to the middle and working class over 10 years, according to the nonpartisan Tax Policy Center. The legislation also excluded the poorest of American households — the very bottom of the income distribution that does not make enough to see their tax burden offset. The measure was criticized from the right as being too expensive. Harris has said the legislation would be paid for by repealing the 2017 GOP tax law, although many Democrats, including Biden, have called for only a partial repeal of that law.

The LIFT Act reflected Harris’s efforts to appeal to voters to the left of Biden on multiple measures while stopping short of a full embrace of the economic policy agenda of Sen. Bernie Sanders (I-Vt.). On health care, Harris said she supported Medicare-for-all before eventually backing off single-payer and supporting a lengthy transition to a government-run system. Biden has rejected the single-payer approach and proposed a more limited public option. On climate, Harris called for a carbon fee for polluters and helped introduce the Green New Deal to spend trillions to spur clean energy — measures Biden has not endorsed.

Vice-presidential picks often have differing policy views from the other person on the ticket, and they typically follow the lead of the presidential contender when it comes to a campaign platform. But Harris’s past proposals will probably face sharp scrutiny during the campaign, from both Democrats and Republicans, as they try to decipher what type of vantage point she would bring to policy debates if Democrats win in November.

Conservatives have said Harris’s policies would add trillions to the national debt while expanding the federal government’s involvement in daily American life. Critics to her left have said she would not go far enough to rectify inequality and provide adequate government benefits to the poor, and have questioned her ties to wealthy Democratic Party donors and the party’s establishment.

Harris’s rent proposal on its own would probably cost about $500 billion per month, or as much as $5.5 trillion a year, said Brian Riedl, an economic policy analyst at the Manhattan Institute, a right-leaning think tank. It would amount to a limited and temporary universal basic income, an idea once confined to the left of the party, and on its own cost about the entire federal budget before the virus. Proponents of the plan, including Sanders and Sen. Edward J. Markey (D-Mass.), have pointed to other countries that have adopted similar measures in response to the pandemic.

“Harris is many things, but please do not use ‘moderate’ or ‘pragmatic’ to describe someone whose own campaign proposed approximately $40 trillion in new spending over the decade,” Riedl said.

JPMorgan Chase has described Harris’s economic policy as consisting of “largely centrist views,” pointing out her opposition to the North American Free Trade Agreement, support for a corporate tax hike and opposition to a single-payer health care system.

Briahna Joy Gray, who served as a spokeswoman for the Sanders campaign, criticized Harris’s economic policies. She pointed to a complicated plan to provide limited student debt relief for some entrepreneurs who meet select criteria — short of the more sweeping measures pushed by Sanders and Sen. Elizabeth Warren (D-Mass.) — and to Harris not backing their sweeping plans for a “wealth tax" on the richest Americans.

“Harris’s means-tested policies leave out some of the most vulnerable among us,” she said. “I don’t have a great deal of confidence that differences between her campaign platform and Biden’s mean that she will push him left on those issues.”