OLYMPIA, Wash. — Washington bars and bowling alleys will be smoke-free starting next month, after voters overwhelming passed one of the most restrictive statewide bans on indoor public smoking in the country.

As of early Wednesday, with about 62 percent of the expected vote counted, 686,981 voters, or 63 percent, supported the more restrictive statewide ban on indoor smoking, while 411,591 voters, or 37 percent, opposed it.

"People saw how their friends and families were going to be protected," said Mike O'Sullivan, spokesman for the American Cancer Society, and backer of the initiative. "It's an easy measure for them to support because they understand the health impact."

Backers of Initiative 901 argued that a more restrictive statewide ban on indoor public smoking was long overdue, citing health concerns and pointing to other states that have already made the change.

Proponents of I-901 were celebrating the results Tuesday night at Kells Irish Restaurant & Pub, a Seattle bar that became smoke-free June 1 after owners took a vote on their Web site and found 85 percent of their patrons wanted them to eliminate smoking.

"I was expecting a little bit of a hit, but we had no hit at all," said owner Patrick McAleese.

The initiative calls for prohibiting smoking in bars, restaurants, bowling alleys, minicasinos, most hotel rooms and most other nontribal businesses currently exempted by the state's Clean Indoor Air Act, which already bans smoking in most public places. It also contains a provision for a 25-foot smoke-free buffer around doorways, windows that open and ventilation intakes.

First-time violators will face warnings. After that, each violation will be punishable by a maximum $100 fine. The measure calls for offending businesses to face suspension of licenses to operate and serve liquor.

Opponents called it an affront to small business owners, who should hold sway over what goes on inside their doors.

The shrinking population of smokers around the country has helped prompt smoking bans elsewhere. Statewide bans that include bars are in place in eight states: California, Connecticut, Delaware, Maine, Massachusetts, New York, Rhode Island and Vermont.

Five states require all restaurants to be smoke-free, but exempt bars: Florida, Georgia, Idaho, Montana, Utah. North Dakota and South Dakota have banned smoking in workplaces, but not restaurants or bars. Many cities and municipalities have imposed their own smoke-free regulations.

In California, the ban on smoking in bars simply moved many smoking sections outside. But I-901's 25-foot rule would effectively ban smoking on many outdoor patios and sidewalks.

Supporters say businesses could work with local health departments to get waivers to the 25-foot rule.

Supporters of the initiative raised more than $1.5 million — much of it from the American Cancer Society. The small but vocal opposition raised less than $27,000.