Billionaire investor and Democratic bankroller George Soros donated $1 million to support legalizing marijuana use in California. The money comes as state voters have begun to turn against the measure, Proposition 19 on the Nov. 2 ballot, that would allow recreational pot smoking in the Golden State.

Mr. Soros, who has largely sat on the sidelines this year as Democrats face a likely thumping at the polls, cut a check to Drug Policy Action Committee to Tax and Regulate Marijuana – Yes on Prop. 19, blank”>according to a filing with the California Secretary of State.

Likely voters opposed the measure 49% to 44%, according to a recent poll by the Public Policy Institute of California. The survey’s margin of error is 3.5 percentage points.

The head of Soros Fund Management has been a long time supporter of loosening marijuana laws. He backed the California’s 1996 medical marijuana and defended the ballot initiative in an op-ed today in >The Wall Street Journal.