HARRISBURG — A state senator who helped win passage of a new state law banning most indoor smoking in public places vowed Wednesday to fight to plug the loopholes that remain.

Sen. Stewart Greenleaf said he plans to introduce a bill in January to amend the law that takes effect today and make the ban complete.

The law forbids lighting up in most workplaces and public spaces, including restaurants, train stations, office buildings and sports arenas. But it also authorizes the state to grant exemptions for certain operations, including private clubs; casinos; nursing homes; bars where food accounts for no more than 20 percent of annual sales; and as many as 25 percent of the rooms in hotels and motels,

Greenleaf, a Montgomery County Republican who has pushed for no-smoking legislation for 15 years, estimated that the new law will apply to 95 percent of all businesses and establishments. He said he expects his colleagues who resisted a stricter ban will get pressure from constituents to expand the prohibition in the coming months.

"Now that we've got 95 percent, it'll be a lot easier to get the other 5 percent," he said after a Capitol news conference on the new law. "It's not going to take 15 years to do it."