(Updated June 17 with latest arrest figures from Missouri Highway Patrol)

In the next week or so, pollsters will be contacting Missouri residents to ask if they support the idea of legalizing marijuana -- and, if so, under what circumstances.

Their responses could determine whether such a proposal appears on the 2016 statewide ballot.

The Missouri secretary of state’s office has approved two initiative petitions that seek constitutional amendments to legalize marijuana production, use, sale and distribution. But the poll could determine whether either of those petitions is circulated to collect the necessary signatures.

John Payne, executive director of the Missouri-based group “Show Me Cannabis,” says the initiatives reflect “our ideal, to legalize and regulate cannabis similar to alcohol.”

But if the poll indicates that Missourians aren’t ready for that, the group may file a new initiative petition proposal with a narrower focus – such as legalizing marijuana for medical use.

“Missouri is a fairly conservative state,’’ Payne explained.

Still, the political climate may be changing. Gov. Jay Nixon, for example, appears to have suffered little blowback for his recent decision to commute the life sentence of Jeffrey Mizanskey, of Sedalia Mo., who has been in prison for roughly 20 years for marijuana-related offenses.

Marijuana legalization growing

Marijuana laws already have softened a bit in Missouri, where jail time is no longer imposed on people convicted for possession of less than 10 grams of the substance.

But many states are going much further. According to Governing magazine, 23 states have legalized marijuana for at least some uses, primarily medical.

Governing magazine

Four of those states -- Colorado, Washington, Oregon and Alaska – have legalized marijuana for recreational use. And some of their state officials are now looking upon the newly home-grown drug as a cash crop.

In the state of Washington, for example, the Seattle Times reports that legislative budget-writers are counting on collecting $1.1 billion in marijuana-related income (mainly new taxes) over the next four years in order to balance the state government’s budgets.

And Colorado’s boom is believed to be affecting the drug trade in Missouri. Payne with “Show Me Cannabis” contends that most of Missouri’s illegal marijuana products are now obtained by the distributors legally in Colorado.

“It’s closer” and safer, he explained, than the old marijuana gateways of Mexico and Canada.

Missouri’s strange bedfellows

Missouri’s potential 2016 ballot battle for some sort of marijuana legalization already has created an “Odd Couple’’ coalition of backers.

Payne says the advisory board for “Show Me Cannabis’’ includes such diverse groups as the American Civil Liberties Union, the St. Louis Tea Party, the United Food and Commercial Workers union and the Epilepsy Foundation.

Supporters also are confident they can raise the money needed for an initiative-petition drive, and for any media campaign. So far, “Show Me Cannabis’’ and its newly formed campaign committee – called “A New Approach for Missouri’’ – has less than $35,000 in their bank accounts, Payne said.

But he added that there are backers ready to bankroll the effort if the poll’s results look promising.

“Show Me Cannabis” was incorporated under the IRS’ 501C4 provision, which means the group doesn’t have to identify its donors or how much it raises or spends. However, the “New Approach” campaign arm already has filed paperwork with the Missouri Ethics Commission, which means its finances will have to be publicly disclosed.

Backers’ chief pitch for legalizing marijuana center on two arguments:

That millions of tax dollars are wasted to handle the more than 20,000 Missourians who are believed to be arrested in the state each year for marijuana-related offenses.

That keeping the plant illegal hurts “people who have very serious illnesses who could benefit from using medical cannabis,’’ Payne said.

Overall statewide arrest tallies for marijuana-related offenses are hard to obtain. The Missouri Highway Patrol reports that its 2014 figures for pot-related arrests show 4,082 misdemeanor arrests and 84 felony arrests for possession of marijuana. The patrol seized 1,700 pounds of marijuana last year.

Controversy continues over marijuana and its medicinal uses. Supporters cite studies showing that marijuana can help in the treatment of epilepsy and some eye diseases, such as glaucoma, and also helps ease the effect of debilitating cancer treatments.

Critics contend the benefits are overblown. For decades, marijuana has been portrayed as “a gateway drug’’ to more serious illegal substances, such as cocaine and heroin. Opponents of the current legalization drive also emphasize that the current crops of marijuana circulated today are much more powerful than the type sampled by many Baby Boomers decades ago.

Payne – who emphasizes that he no longer uses the drug – says few people now partake of the old-school marijuana “joints’’ of the 1960s and ‘70s. Now, the drug usually is consumed in much smaller amounts, via vaporizers or pipes.

So far, there appears to be no organized opposition in Missouri, but Payne expects that to change should a legalization proposal actually make the 2016 ballot.

Is traditional opposition softening?

Law enforcement has been traditionally been the most vocal critics of easing marijuana laws, but even that may be softening.

The Missouri Highway Patrol, which has taken the lead of the state’s anti-drug efforts for decades, isn’t taking any position on any marijuana legalization proposals, a spokesman said.

Jason Rosenbaum | St. Louis Public Radio

St. Louis Circuit Attorney Jennifer Joyce, for example, said in an interview last week that she might be open to some sort of legalization if provisions are made to bar use among drivers “and children aren’t exposed to it."

With “sensible precautions like that, I would not necessarily be opposed to it,” Joyce said. She added that she was paying close attention to what happens in Colorado -- where her daughter lives -- now that marijuana has been legalized.

Such an attitude contrasts sharply with those in 1992, when there was a national uproar over then-presidential candidate Bill Clinton’s acknowledgement that he had used marijuana in college, even though he contended he didn’t inhale.

And in Missouri in 1992, a political tempest ignited during a formal debate in St. Louis featuring the Republican and Democratic candidates for state attorney general.

In response to a panelist’s question, a majority of the contenders – including Nixon – acknowledged that they had sampled marijuana in college back in the 1970s. Nixon’s GOP rival, David Steelman, later sought to use the Democrat’s admission as an issue in the general election.

That backdrop may be a help now for legalization backers. Payne said that polls conducted elsewhere show that legalization support is strongest among the under-35 crowd, and the Baby Boomers, now in their 50s and 60s.

Voters age 70 and older, Payne said, generally have been the staunchest opponents to changing marijuana laws. When it comes to legalization, he said, “One of the biggest dividers is age.”