A contingent of supporters, including restaurant and bar employees, made their case before the Senate Finance Committee on Thursday.
"As a legislature, we have a responsibility to protect the workers in this state," said Sen. Ida Ruben, D-Montgomery, the bill's lead sponsor. "Don't wait 'til this life-threatening carcinogen kills more people."
Supporters of the ban cited a December poll that found support for the ban among 67 percent of registered Maryland voters.
New York City restaurant owner Mike O'Neal testified that his business increased when smoking was banned from restaurants in 1995 and bars last March.
Those statistics contradicted those offered by Binau, who said Delaware slots parlors lost 22 percent of their business after a ban went into effect there.
"If everybody loses 22 percent, that's tough," he said.
Ruben and other advocates argued that the health of bar and restaurant employees is more important than money.
Also, Ruben said the ban could save money by reducing health-care costs in the long run.
One local lawmaker serves on the Finance Committee. Sen. John J. Hafer, R-Garrett/Allegany/Washington, could not be reached for comment after the hearing.
Last year, the committee defeated the bill. Its chairman, Sen. Thomas Middleton, is a Democrat from Charles County, where tobacco farms are plentiful.