Voters in San Francisco and three other cities overwhelmingly approved by-the-ounce soda taxes, upgrading Philadelphia's status overnight from outlier to soothsayer in a trend that proponents hope will establish a new kind of sin tax.

Philadelphia five months ago became the first big city to approve a sweetened-beverage tax, set at 1.5 cents an ounce.

On Tuesday, Boulder, Colo., easily passed a 2-cent tax.  And residents of San Francisco and neighboring Bay Area cities of Oakland and Albany favored penny-per-ounce levies by margins of 60-40 or more.

None of them are typical of the nation as a whole; Hillary Clinton took 70 percent of the vote in these cities. But the industry fought hard to stop its losses, reportedly spending more than $21 million fighting the proposal in San Francisco alone – twice what it spent lobbying against the Philadelphia tax.

Spending by both sides in San Francisco and Oakland topped $50 million.

All four  target beverages with added sugar, as does the only significant beverage tax now in effect in the U.S., Berkeley, Calif.'s penny-per-ounce levy. Proponents framed their campaigns for all of them largely as anti-obesity measures.

Mayor Kenney, by contrast, argued for his tax mainly to raise revenue to expand pre-kindergarten and other popular programs. City Council broadened it to include artificially sweetened beverages.

Michael Bloomberg, who tried unsuccessfully to ban jumbo soft drinks when he was mayor of New York, gave $1.6 million toward lobbying efforts in support of Kenney's tax, and he was also a major donor for the latest measures, although the industry spent more. The American Beverage Association in September filed suit  to prevent the Philadelphia tax from taking effect as scheduled on Jan. 1; the state Supreme Court last week turned down a request to immediately take up the issue, leaving it in Common Pleas Court.

The tax will be paid by distributors. If they pass the full cost on to consumers, the price of a 20-ounce bottle of soda would rise by 30 cents.

When the tax was passed, some advocates predicted that Kenney's strategy would be adopted elsewhere. It was too late to easily make changes in the initiatives that appeared headed for approval in Wednesday's elections.

"This vote is an historic turning point in the effort to bring sugar back to healthy levels," said Jim Krieger, executive director of Healthy Food America, a Seattle, Wash.-based nonprofit that posts a track-the-movement map on its site.

Coca-Cola Co., PepsiCo Inc. and other companies in the roughly $100 billion U.S. soft drink industry point to their efforts to reformulate products and broaden the range of drinks they offer to address consumers' health concerns. More than one-third of American  adults are obese.

"Our energy remains squarely focused on reducing the sugar consumed from beverages," a spokeswoman for the American Beverage Association said in an emailed statement. Consumption has been declining for several years even without higher prices.

The next test may be in Illinois. Commissioners in Cook County are now considering a penny-per-ounce tax that resembles Philadelphia's in two key ways: It was pitched  to raise revenue, and would include diet as well as regular soft drinks. A vote could come as early as Thursday.

This post includes information from Reuters.

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