Polling now suggests that, if the vote were taken today, the Proposition 19 legalization ballot initiative would pass--Field Research shows 49 - 42 percent support, while Public Policy Polling shows Prop. 19 passing 47 - 38 percent--and pressure is already mounting on the White House to sue California if it does, just as Attorney General Eric Holder's Justice Department is now suing Arizona over its controversial SB 1070 immigration law.





Earlier this month, nine former administrators of the Drug Enforcement Administration sent a letter calling on Obama and Holder to sue if Prop. 19 passes, blocking the statewide legalization of possession and personal growth and the allowance of individual counties to license commercial sale and production of marijuana.





A lawsuit may not be so simple--the federal government may have a better case against Prop. 19's commercial provisions than its sections on personal use--but regardless, if Prop. 19 passes, Obama and Holder will have to decide what to do.





The pressure will likely be intense. Legalized marijuana is practically inconceivable to large swaths of the country, and one can see the broader coalition of social conservatives and concerned moderates reeling in shock on November 3, aghast at California's decadence and lawlessness, and turning to President Obama to put a stop to it.





Make no mistake: the legalization of marijuana in the country's largest state by population, with governmentally sanctioned commercial grow-houses and open storefronts (which will probably arise, according to one longtime marijuana advocate, in Oakland, West Hollywood, and maybe one other county) would be a major change in this country. Commercial distribution of medical marijuana already happens in a few places around the country, and it's allegedly pretty loose in California and Colorado. But outright legalization is a different thing entirely.





If Obama doesn't take action, he'll be seen as the president who let this happen. It could very well lead many people to vote against him in 2012.





At this point, it seems the Obama administration will sue California, but that's just an educated guess: the Justice Department has declined to comment. Obama's drug czar, former Seattle Police Chief Gil Kerlikowske, has weighed in firmly against legalization on a national scale, and he submitted an op-ed to the L.A. Times co-authored with several former drug czars (some of whom have taken a very hard line against medical marijuana) warning that Prop. 19 would increase social costs by leading to more marijuana use.





But while standing on the sidelines would probably damage Obama with many voters, a lawsuit could bring its own political costs.