With the nation facing an economic calamity, an unlikely group of politicians, ranging from President Trump and Sen. Mitt Romney to Sen. Kamala Harris and Rep. Ro Khanna, is lining up behind a measure Stockton put in place a year ago: Giving money directly to people, no questions asked.

The cash payments are likely to be included in a $1 trillion-plus coronavirus stimulus package that Congress will take up in the coming days. How much people would receive, and whether there would be restrictions based on income, is in flux.

What’s not in question is bipartisan support for the idea of directly sending cash to Americans, a concept that was largely a progressive fringe cause until former candidate Andrew Yang promoted it during the Democratic presidential campaign. Early advocates of a universal basic income argued that even under normal circumstances, 40% of Americans couldn’t afford an unexpected expense.

Now, Congress is dealing with anything but normal circumstances. Treasury Secretary Steve Mnuchin said this week that unemployment could hit 20% if lawmakers failed to pass a stimulus package that included cash payments to Americans.

“It’s needed and it shouldn’t be a one-time thing,” said Stockton Mayor Michael Tubbs, whose city began giving $500-a-month payments to 130 families in February 2019 as a pilot program for universal basic income. Based on his experience with the privately funded program, Tubbs said, national payments should continue “for at least as long as this crisis is going on.”

The Trump administration, however, has other ideas. It is proposing to send two installments of equal amounts to Americans, on April 6 and May 18, NBC reported. The payments would be based on a family’s size and income level.

Trump declined to offer specifics at a news conference Wednesday because there are “different numbers” being discussed.

“We want to go big,” Trump said.

So does a group of Democratic House members led by Khanna, a Fremont Democrat who is a national co-chair of Sen. Bernie Sanders’ presidential campaign. He is proposing legislation that would give from $1,000 to $6,000 to every American who earned less than $65,000 last year. Under Khanna’s plan, those recipients could receive monthly payments after that.

“This plan is about providing real, urgently needed relief to middle- and working-class families,” Khanna said in a statement. “If we can afford to pump $1.5 trillion into lending markets, then we can afford this solution to help every American.”

A group of 18 Democratic senators, including Harris, is offering a slightly different plan. It would give an immediate payment of $2,000 to nearly every American, followed by another payment of $1,500 in July if economic conditions remain dire. A third installment of $1,000 could come in October. Higher-income Americans would gradually be phased out of the program.

The California senator said two coronavirus stimulus packages that Congress has passed so far are “steps in the right direction, but we need to do much more to help working people.”

Support for the general concept of direct payments is coming from across the political spectrum. Romney, R-Utah, has called for giving every adult $1,000. Sanders, I-Vt., wants to give $2,000 monthly to “every person in America” for “the duration of the crisis.”

The federal government has done this before during economic downturns. Nearly every American received a $300 check in 2001 during a slowdown and most received $300 to $600 as a recession started in 2008.

But UC Berkeley economics and law Professor Alan Auerbach cautioned that giving cash to everyone isn’t a panacea for the coronavirus-caused downturn.

“I’m tempted to call this the political equivalent of panic buying,” said Auerbach, director of the Robert D. Burch Center for Tax Policy and Public Finance. “But I understand its motivation, and given the circumstances, it is better than doing nothing.”

He said there is a “natural inclination to do something big and fast,” but actions more targeted at industries being hit especially hard would be more effective.

Cash payments to people won’t keep those industries alive, Auerbach said. “If you give me $1,000, I’m not going to take a cruise.”

Increasing or extending unemployment benefits would more directly help workers affected by the virus, Auerbach said. The federal government should increase Medicaid payments to the states, which will need more resources to help low-income residents hurt by the slowdown, he added.

Mayor Tubbs, however, said an infusion of cash will help people who live in cities like Stockton, which has a poverty rate of 22%.

“Our elected officials aren’t treating this as a pandemic because people in their peer group are millionaires,” Tubbs said. But in Stockton, “this is dire.”

Yang campaigned on giving every American a universal basic income of $1,000 a month. He said Wednesday that he was happy to see the idea gain acceptance, even though, “I would never wish for these circumstances.”

“I never dreamed that I would suspend my campaign in February, then we would be implementing universal basic income in March,” Yang said on CNN, adding that his team has been in touch with the White House on the issue. “Putting money into people’s hands will keep us afloat.”

Joe Garofoli is The San Francisco Chronicle’s senior political writer. Email: jgarofoli@sfchronicle.com Twitter: @joegarofoli