The subsidy is part of the federal Essential Air Service program, which provides incentives for airlines to serve airports in small communities.
U.S. Sen. Benjamin L. Cardin, D-Md., introduced a bill Aug. 2 that would extend the federal program for five years.
As of Wednesday, the bill had not moved from the Senate Committee on Commerce, Science and Transportation, where it was assigned after it was introduced.
Larsen said the airport is "looking to the EAS bill as the thing that will keep service in place."
The airport, which was founded in 1927, has not been without a commercial airline since it began passenger service in 1931. However, it has had three different carriers in five years.
Chautauqua Airlines suspended service at the airport in May 2002 after the company switched its fleet from small commuter planes to regional jets.
Chautauqua's sister company, Shuttle America, took over service at the airport until May 2004, when the company stopped flying for US Airways.
Air Midwest has provided service at the airport since then but has received the $650,000 annual subsidy to do so for the past two years.
"It just wouldn't be financially viable to fly there without it," Bacon said in August.
In a statement released Wednesday afternoon, Airport Manager Carolyn Motz said the airport's passenger terminal, which houses three rental car agencies, will operate normally.
Hina Qureshi, owner of Avis Car Rental at the airport, said her business will stay open.
"We will probably lose some business. But we're going to stick around. They're planning to get another carrier soon."
Larsen said he does not think the airport will cut any jobs because of the loss of passenger service.