Pot is very much on the minds of voters, with millions poised to decide whether to legalize it. That raises a tantalizing question for presidential candidates: Is there political opportunity in the wind?
Some are beginning to believe there is.
The latest sign was the full-throated call last week by Sen. Bernie Sanders to end federal prohibition. With that one move, the candidate for the Democratic presidential nomination plunged into uncharted territory — and, arguably, so did the presidential race.
Never before has a contender with so much to lose so unequivocally suggested that smoking a joint should be viewed the same as drinking a beer, at least in the eyes of the law.
The move was about more than Sanders' signature straight talk. It could give the Vermont senator a much-needed boost in some primary states, especially in the West.
Some pollsters and strategists are surprised it has taken this long for a leading candidate to promote legalization this forcefully.
"Politicians are terrible at anything new," said Celinda Lake, a Washington political strategist who has worked on pot initiatives. "They always miss the trends where voters are ahead of them."
She says voter opinion is shifting on marijuana as rapidly as it did on same-sex marriage, another issue where lawmakers struggled to keep pace with evolving public attitudes.
A new Gallup poll found that 58% of voters say marijuana should be legalized, suggesting there is not a lot of risk in embracing it. More important, the pot vote draws a demographic highly coveted by campaign operatives: It's young, diverse and up for grabs.
But there may be danger in doubling down on the dime bag.
"It can easily be turned against them," said Kevin Sabet, president of Smart Approaches to Marijuana, an anti-legalization group.
What happens, he asked, when a pro-pot candidate is confronted at a town hall by the parent of a child who had a "psychotic episode" after consuming a pot lollipop? "How do you defend against that?"
The candidates are grappling with legalization at the same time that drug abuse is a prominent issue in the primaries, with a heroin epidemic a key concern of voters in Iowa and New Hampshire, the first two states to hold contests.
Republican contender Carly Fiorina has spoken emotionally about losing her stepdaughter to addiction.
And there is disagreement among strategists about just how rapidly public opinion has shifted in the voting groups that count most in a closely contested election, such as Latinos and older women.
"There are too many battleground states where it is still controversial," said Anna Greenberg, a Democratic pollster.
Sanders framed his language carefully. "Too many Americans have seen their lives destroyed because they have criminal records as a result of marijuana use," he said at George Mason University in Virginia on Wednesday. "That's wrong. That has got to change."
He said he would take marijuana off the federal government's list of illegal drugs, leaving states free to regulate it the way they do alcohol and tobacco.
Kentucky Sen. Rand Paul, a Republican, has taken a similar plunge, but the stakes are higher for Sanders, who is far more popular with voters.
Other candidates are fumbling their way forward.
Hillary Rodham Clinton has told small audiences in the pot havens of Oregon and Colorado that marijuana businesses in states where it is legal need relief from federal restrictions that can make it impossible for them to operate.
Yet her campaign refused to accept a donation from the cannabis industry's trade group, and in the first Democratic debate she took a "wait and see" position.
Some Republicans, including New Jersey Gov. Chris Christie and Ohio Gov. John Kasich, aggressively oppose legalization. Christie, a former federal prosecutor, has taken the hardest line, vowing a crackdown. Other Republicans say they would let states continue experimenting.
"Politicians have been three steps behind the public on this," said Rep. Earl Blumenauer (D-Ore.), a leading legalization proponent in Congress. "The train is already leaving the station. There is huge opportunity. It is going to be on the ballot in swing states."
The impact on political candidates was unclear when legalization came before voters last year. Alaskans voted to legalize recreational use while also electing a Republican senator, Dan Sullivan, who opposed the move.
Oregonians also voted to legalize, while at the same time reelecting an incumbent governor, Democrat John Kitzhaber, who did not support legalization.
In Florida, Democrats had hoped a popular medical marijuana measure would give them the edge in the 2014 governor's race. It didn't. Although 58% of voters supported medical marijuana, Republican Rick Scott won the gubernatorial election.
Those bullish on the boost that pot can provide say the landscape will be dramatically different in 2016, a presidential election year, when turnout is expected to be younger and more diverse — and candidates like Sanders and Paul are not tiptoeing around the issue.
Legalization for recreational use is expected to be on the ballot in Arizona, California, Maine, Massachusetts and Nevada.
The state being watched most now, though, is Ohio. Voters in that battleground state will decide on a legalization measure Tuesday. Candidates will closely monitor the outcome.
"This is the gay marriage issue of the day," said John Morgan, an Orlando, Fla., trial lawyer, who spent more than $4 million of his own money on the Florida medical pot measure. It fell short of meeting the state's unusually high threshold of 60% for an initiative to pass.
So Morgan is bankrolling another measure for next year.
In late spring, he hosted a fundraiser at his home for Clinton.
"Many of them are not leaders, they're followers," he said of politicians. "We saw that on gay marriage and other issues, and now we'll probably see it on marijuana at some point. At some point they'll say 'whatever' and go along with what's right."
Halper reported from Washington and Lee from Los Angeles.