On Nov. 2, California voters will take to the polls to decide upon a controversial ballot initiative, the legalization of marijuana. Under Proposition 19, also known as the Regulate, Control and Tax Cannabis Act of 2010, various marijuana-related activities would be legalized under state law and local governments would be authorized to collect taxes related to marijuana.

Supporters of Proposition 19 focus on the fact that legalization would provide the state with a much-needed source of revenue; Californians spent approximately $1.4 billion annually on marijuana. Because these sales are not legal, these commercial transactions go untaxed. Legalization could provide significant revenues to struggling local governments.

In addition to the revenues generated, supporters of the measure argue that legalization would decrease the costs of enforcing existing drug laws. Furthermore, some have argued that legalization could help to end the drug problems in Mexico.

Opponents remain unconvinced that Proposition 19 is the appropriate solution to these challenges. Some have expressed concerns that the ballot proposition is poorly drafted, thereby making it a weak platform for such a significant change. Because the proposition would allow each county to make its own regulations for the sale and possession, it could lead to confusion. Finally, some fear that legalization would lead to more widespread use of the substance, and believe that this should be discouraged.

At the moment, though, it is nearly impossible to predict what might come of Proposition 19. According to Nate Silver of the New York Times, the polls slightly favor the opponents at this point, with 47 percent planning to vote no and 46 percent planning to vote yes. However, he also notes that ballot issues are very difficult to poll, and that prior models may not properly account for a variety of issues that might affect the outcome.

For example, many people who might not otherwise vote may be particularly inclined to vote because this issue is on the ballot. The state is also in the midst of a hotly contested gubernatorial race, and the turnout for that race may have unexpected consequences for this ballot measure. Ultimately, Silver reports about even odds for the success or failure of this initiative, and only time will tell what might be to come in California.

Of course, even if California opts to legalize marijuana under state law, this would not alter federal laws. Under the federal Controlled Substances Act, it is illegal to possess, cultivate, use or distribute marijuana, and Attorney General Eric Holder has made it clear that the Obama Administration will "vigorously enforce" federal drug laws, regardless of how the state laws may change. As a practical matter, though, this might be an empty threat for those who possess limited quantities of marijuana, as it would likely be too costly for the federal government to prosecute every case. Alternatively, the federal government may seek an injunction against Proposition 19 if it passes, requesting that the courts prevent it from taking effect.

Should Proposition 19 pass, though, it would likely initiate a national conversation on the legalization of marijuana in this country, thereby helping to pave the way for other states seeking to introduce similar measures. Certainly, it will not be an immediate shift, and some states may be closer to legalization than others.

One might reasonably assume that those states with existing medical marijuana laws might be more likely move to full legalization than those still seeking to enact medical marijuana laws, such as Wisconsin. For those with strong feelings on legalization of marijuana though, now is the time to be heard, as the true debate on the issue begins.