It could take days before California counts all the votes in a controversial proposal that would add a steep tax to cigarettes, but an unofficial count currently shows it narrowly defeated.

According to California's secretary of state, 50.8 percent of voters said no to Proposition 29, and 49.2 voted in favor -- a difference of about 63,000 votes. California, which hasn't raised cigarette taxes in 14 years, considers any contest with less than 2 percentage point difference in results a close contest and won't declare a result unless that gap increases.

Although all precincts were reporting, the Associated Press reported that late-arriving ballots still could comprise up to 20 percent of the votes.

There is already an 87-cent per-pack tax on cigarettes in California.

Polls from weeks ago showed that California was largely in favor of the measure, which promises to bring in about $855 million the first year it is implemented. A Public Policy Institute of California survey from March showed that 67 percent supported Prop 29.

Since then, however, tobacco companies have poured millions of dollars in an advertising push against the proposal. Another poll in May found that support for Prop 29 had dropped to 53 percent. The tobacco industry outspent its opponents 4 to 1 by largely financing $47 million in ads, the Boston Globe reported.

California has long had a reputation for having tough anti-smoking laws. It boasts having the second-smallest percentage of smokers in the country -- 11.9 percent last year -- and is only superseded by Utah's 9.1 percent.

The proposal attracted the likes of public health champion Michael Bloomberg, New York City's mayor, who contributed $500,000 to the campaign. New York City banned smoking in restaurants and bars in 2002 and in public parks and beaches in 2011, and Bloomberg has proposed a ban on the sale of large sodas and sugary drinks in most businesses.

Bicycling champion Lance Armstrong, a cancer survivor, has also taken part in a public relations initiative to pass the tax hike.

Advertising California New York Michael bloomberg