Will there be a fourth stimulus check? Here's what we know so far

As the IRS sends out the last of the third round of stimulus checks and tops off payments for millions of other Americans, some lawmakers are already pushing for a fourth check.

The third stimulus payments — worth up to $1,400 per individual and each of his or her dependents — currently being delivered by the IRS will help many families with bills like rent and groceries.

But while finances for many American households are improving, millions are financially struggling more than a year after the first coronavirus-induced shutdowns. Almost 30% of Americans couldn't cover all of their household expenses in late March, according to the latest U.S. Census Bureau data collected March 17-29. About 18 million adults are still going hungry each month.

The continued economic fallout from the pandemic is why a group of 21 Democratic Senators recently sent a letter to President Joe Biden asking him to include recurring direct payments and automatic unemployment insurance extensions in his long-term economic plan.

The lawmakers, including Senate Finance Committee Chair Ron Wyden, D-Ore., and Budget Committee Chair Bernie Sanders, I-Vt., argue that the third stimulus payment, a provision of Biden's $1.9 trillion American Rescue Plan (ARP) signed into law in early March, would not last many cash-strapped families long.

So far, Biden has not indicated publicly that he supports a fourth stimulus payment. For now, the president seems focused on passing his $2 trillion-plus infrastructure plan that aims to improve transportation infrastructure and affordable housing, among other things.

"This crisis is far from over, and families deserve certainty that they can put food on the table and keep a roof over their heads," the Senators wrote in their letter. "Almost 6 in 10 people say the $1,400 payments set to be included in the rescue package will last them less than three months," they said.

Their letter follows a similar overture from some Democratic House members advocating for monthly payments until the economy fully recovers.

Direct payments reach people who need immediate aid

Direct payments, in particular, help those who do not qualify for unemployment insurance but have had their hours reduced or left their job to care for family members during the pandemic, economists have said.

Direct payments have helped alleviate poverty in the U.S., and a fourth stimulus check alone would lift 6.6 million people out poverty in 2021, according to a recent report from Elaine Maag and Kevin Werner at the Urban-Brookings Tax Policy Center.

"Housing instability and food insecurity remain concerns for many, and an additional payment could help with both," Maag writes to CNBC Make It in an email, noting that Black and Hispanic families with children feel the pain more acutely than other households. "Studies on how other economic impact payments were spent indicate people spent the money on necessities like food, housing and bills."

That said, with the vaccine rollout chugging along and more states lifting coronavirus restrictions, it is not clear if the progressive lawmakers will be able to sell the idea to their more moderate or conservative colleagues.

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