So will presidential hopefuls come out joints blazing in 2016? That remains to be seen. Here's where the candidates stand now:

Hillary Clinton

Position: Against decriminalization. During the 2008 Democratic primary, the former Secretary of State gave this statement: "I don't think we should decriminalize, but we ought to do research into what, if any, medical benefits it has."

Change: None yet. It's hard to imagine she'll be able to stick with this line in light of Obama's recent statements.

Martin O'Malley

Position: The Democratic governor is skeptical of decriminalization. He's said he's "not much in favor" of reducing criminal penalties for possession, and he once threatened to veto Maryland's medical marijuana law.

Change: None yet, but O'Malley will be confronted with the decriminalization issue sooner than expected. The Maryland House just voted to decriminalize possession of small amounts of pot on Saturday.

Update, 5:03 pm: The Washington Post reports that O'Malley is now expected to sign the decriminalization bill into law.

Joe Biden

Position: Smarter enforcement, not legalization. After accidentally making his gay marriage position known before the president could weigh in, Biden's been careful not to get out in front of Obama on weed. He told Time in February, "I think the idea of focusing significant resources on interdicting or convicting people for smoking marijuana is a waste of our resources. That’s different than [legalization]. Our policy for our Administration is still not legalization, and that is [and] continues to be our policy."

Change: No. In 2010, he called pot a "gateway drug." He has not amended this statement.

Jeb Bush

Position: Unclear. The current Republican frontrunner hasn't spoken recently about this issue. In 2002, he opposed treatment instead of jail for nonviolent drug offenders. (Some called this hypocritical, as his daughter Noelle was busted for crack cocaine around the same time.)

Change: Not yet.

Rick Perry

Position: In favor of decriminalization. In January, he told the Texas papers, "After 40 years of the war on drugs, I can’t change what happened in the past. What I can do as the governor of the second largest state in the nation is to implement policies that start us toward a decriminalization and keeps people from going to prison and destroying their lives, and that’s what we’ve done over the last decade." He also thinks states should decide the legalization issue.

Change: Yes. Surprisingly, Perry is one of the first Republicans to really embrace decriminalization. Back in 2008, he criticized the ACLU for protesting random drug sweeps in public housing.

Marco Rubio

Position: Unclear. The Florida senator hasn't weighed in on a medical marijuana referendum in his state. He also won't say whether or not he's ever smoked pot.

Change: Not yet.