WASHINGTON – While a growing number of states have turned their attention to marijuana legalization, another proposal has been quietly catching fire — raising the legal age to buy cigarettes.

This summer, Hawaii became the first state to approve increasing the smoking age from 18 to 21 starting Jan 1. A similar measure passed the California Senate, but stalled in the Assembly. And nearly a dozen other states have considered bills this year to boost the legal age for buying tobacco products.

"It really is about good public health," said Democratic Hawaii state Sen. Rosalyn Baker, who sponsored the legislation. "If you can keep individuals from beginning to smoke until they're at least 21, then you have a much greater chance of them never becoming lifelong smokers."

Supporters say that hiking the legal age would save lives and cut medical costs. Opponents say it would hurt small businesses and violate the personal freedom of young adults who are legally able to vote and join the military.

Measures to raise the smoking age to 21 also were introduced this year in Massachusetts, New York, Oregon, Rhode Island, Utah, Vermont, Washington and the District of Columbia, according to the Preventing Tobacco Addiction Foundation, an advocacy group. Iowa and Texas considered measures to increase the legal age to 19. None of those bills passed. And just last week, a Pennsylvania legislator introduced a bill to up the minimum age there to 21.

In almost every state, the legal age to buy tobacco is 18. Four states — Alabama, Alaska, New Jersey and Utah — have set the minimum at 19.

Anti-tobacco and health care advocates say that hiking the smoking age to 21 is a fairly new approach in their effort to reduce young people's tobacco use. Until recently, research on the topic has been somewhat limited, they say.

That hasn't stopped a growing number of local governments from taking action on their own in the past few years. At least 94 cities and counties — including New York City, Evanston, Ill., and Columbia, Mo. — have passed measures raising the smoking age to 21, according to the Campaign for Tobacco-Free Kids.

One of those communities is Hawaii County, the so-called Big Island of Hawaii, where the law changed last year after a grass-roots effort by health care advocates, anti-smoking groups and local high school students. That coalition, joined by teens from across Hawaii, continued its fight at the state level, and legislators heard the message, said Sen. Baker, whose bill also included e-cigarettes and battery-powered devices that deliver vaporized nicotine, which have become popular among young people.

Supporters of raising the smoking age say that a turning point was a March report by the Institute of Medicine, the health arm of the National Academies of Sciences, Engineering and Medicine, which predicted that raising the age to 21 would cut smoking by 12 percent by the time today's teenagers are adults. It also would result in about 223,000 fewer premature deaths.

Opponents say taxpayers would take a financial hit if the smoking age is raised because it would mean less revenue from cigarette taxes.