If Congress doesn’t resolve a partial government shutdown this week, Transportation Security Administration officers will miss their second full paycheck.

“If we lose another check, it’ll accelerate the number of people walking out and calling out,” said Mike Gayzagian, president of American Federation of Government Employees Local 2617, which represents TSA workers across New England.

On Tuesday, lawmakers were working on a proposal that would fund most of the Department of Homeland Security, including TSA officers, but not the U.S. Immigration and Customs Enforcement operations that have been driving the shutdown that began on Feb. 14.

“First step is to get the proposal in writing,” Maine Sen. Angus King, an independent, told The Associated Press. “I want to see exactly what that means.”

Gayzagian, who is a TSA officer at Boston Logan International Airport, predicts more officers would be forced to quit if the shutdown is not resolved and the workers, who have gone more than a month without being paid, miss another full paycheck. This is the third time these employees have gone without pay during a government shutdown in less than a year.

“Everybody has got a financial clock, and when the clock runs out, that’s it,” Gayzagian said. “I had an officer come up to me and say, ‘I’m down to my last $800, and I have to go.'”

In some cities, airports are reporting significant wait times at security due to staffing shortages. The Department of Homeland Security said nearly 11% of TSA workers missed work Monday, and at least 458 have quit since the shutdown began.

Gayzagian said only a small percentage of officers in Boston and at the Portland International Jetport have resigned. He knows many who have taken on second jobs, including driving for Uber or picking up shifts at towing companies, so they can pay their bills.

The jetport has not experienced the long lines and staffing shortages reported at other airports.

“Portland has been very stable,” Gayzagian said. “It’s a really tightknit group of officers up there. The management and the officers work closely together. They’ve been able to hold on.”

U.S. Transportation Secretary Sean Duffy warned in an interview with CNBC last week that small airports might need to close if staffing shortages worsen, although he did not specify which ones. The federal government has ordered immigration enforcement officers to assist the TSA in some cities.

Zachary Sundquist, assistant director of the Portland International Jetport, said Monday that he is not concerned that the airport would close or require assistance from other federal agencies.

He said officials at the jetport have been accepting donations for the airport’s roughly 125 TSA officers at the entrance of the security checkpoint.

Gayzagian said federal employees have to follow certain rules about accepting gifts, but airport officials, airlines and the union are all working to support workers. The jetport posted on Facebook that it can accept nonperishable pantry items and gift cards for food and fuel for up to $20 to support these workers.

“We remain grateful to our TSA officers who continue to show up and work despite not receiving paychecks,” Sundquist said in an email Tuesday. “We are also appreciative of the care and consideration the community has shown in donating food and gift cards to support our TSA colleagues.”

Gayzagian said the situation at Logan has also remained relatively stable. Donations and even kind words give officers a boost, he said.

“The officers see this, and they say, ‘Maybe I can hold on a little bit longer,'” Gayzagian said.

This story contains reporting from The Associated Press.