Most of the $325 billion that lawmakers are proposing for small business in a new economic rescue package would go toward a new round of Paycheck Protection Program loans, which offer a lifeline to borrowers because they don’t have to pay the money back if they retain their workers.

But while many struggling businesses are desperate for help as the pandemic surges, the resurrection of the program more than four months after it was shut down will only provide short-term support. The small business aid will cover up to three-and-a-half months’ worth of payroll costs — well short of how long many of them expect it will take to bounce back: A Census Bureau survey showed that 46 percent of employers don’t see normal operations resuming for more than six months.

“Small business savings have been exhausted, winter weather has rendered outdoor adjustments useless, and widespread vaccination is not expected until mid-2021,” said Luke Pardue, an economist at payroll services firm Gusto, noting that the original infusion of aid in April ran out in two weeks before being replenished. “Eight weeks of payroll support for the businesses that are fortunate enough to get aid is simply not enough.”