• A growing number of lawmakers is pushing for recurring stimulus checks in an infrastructure plan.
• The Economic Security Project found two more checks would keep 12 million more people out of poverty.
• So far, 28 Democrats have signed letters asking Biden to include recurring checks in infrastructure.
• See more stories on Insider's business page.

Stimulus checks have been a cornerstone of pandemic relief, helping offset financial strains brought on by COVID-19. But studies have shown that those checks only last Americans a few months, and many Democratic lawmakers want to implement recurring direct payments for a sustainable economic recovery.

Under the CARES Act signed into law in March 2020, Americans received their first $1,200 stimulus check. Then came the December $600 check, and most recently, President Joe Biden signed the American Rescue Plan into law, which included $1,400 stimulus checks.

Democratic lawmakers don't want Biden to stop there.

The Economic Security Project found that that sending two more rounds of stimulus checks could keep 12 million more Americans out of poverty, and since the beginning of this year, a growing number of Democrats have come out in support of recurring payments, urging Biden to include them in his infrastructure plan.

For example, in March, 21 senators wrote a letter to Biden advocating for recurring direct payments, and last week, seven House Democrats wrote a similar letter pushing for the same thing.

"The pandemic has served as a stark reminder that families and workers need certainty in a crisis," the House Democrats wrote. "They deserve to know they can put food on the table and keep a roof over their heads. They should not be at the mercy of constantly shifting legislative timelines and ad hoc solutions."

Here are the lawmakers who support recurring stimulus payments in Biden's infrastructure plan, according to letters from House and Senate members:

Senate Democrats

• Tammy Baldwin of Wisconsin
• Michael Bennet of Colorado
• Richard Blumenthal of Connecticut
• Cory Booker of New Jersey
• Sherrod Brown of Ohio
• Dick Durbin of Illinois
• Tammy Duckworth of Illinois
• Kirsten Gillibrand of New York
• Mazie Hirono of Hawaii
• Ed Markey of Massachusetts
• Jeffrey Merkley of Oregon
• Alex Padilla of California
• Gary Peters of Michigan
• Ben Ray Luján of New Mexico
• Jack Reed of Rhode Island
• Bernie Sanders of Vermont
• Brian Schatz of Hawaii
• Debbie Stabenow of Michigan
• Elizabeth Warren of Massachusetts
• Sheldon Whitehouse of Rhode Island
• Ron Wyden of Oregon

House Democrats

• Donald Beyer of Virginia
• Earl Blumenauer of Oregon
• Judy Chu of California
• Jimmy Gomez of California
• Gwen Moore of Wisconsin
• Jimmy Panetta of California
• Brad Schneider of Illinois