Lansing — A ballot initiative to legalize recreational marijuana and retail sales in Michigan remains popular with voters but faces a late push from opponents running television attack ads in an effort to defeat the measure.

A majority of Michigan voters support Proposal 1, according to an Oct. 25-27 poll of 600 likely voters conducted for The Detroit News and WDIV. Fifty-seven percent of respondents said they would vote for the legalization initiative compared with 40 percent who were opposed.

The 17-percentage-point margin bodes well for the Coalition to Regulate Marijuana Like Alcohol, and the findings indicate 2.8 percent of voters remain undecided on the measure. The survey had a margin of error of plus-minus 4 percentage points.

“Voters know where they stand on the issue of legalization,” said Glengariff Group pollster Richard Czuba. “But the one red flag I’d wave here is that if younger voters don’t materialize at the polls, this is going to be a closer proposal than it's polling at right now.”

Early returns suggest opposition among absentee ballot voters, a group that typically includes older voters who are less supportive of marijuana legalization, Czuba said. Proposal 1 polled at 86 percent support among 18- to 29-year-olds but 38.5 percent backing among respondents over the age of 65.

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A ballot proposal to create no-reason absentee voting and same-day voter registration had a comfortable double-digit lead in the same poll. There also was a double-digit lead for a proposal to establish a redistricting commission to draw political boundaries every 10 years instead of the party in power, but Czuba warned a late opposition campaign could make the contest more competitive.

The pro-legalization campaign was outspent by foes in the three months between July 21 and Oct. 21. But both sides are pulling in large, last-minute contributions and plan to spend heavily on advertising in the final week before Tuesday's election.

Healthy and Productive Michigan, the opposition committee endorsed by various law enforcement and prosecutor groups, has reported a slew of recent five- and six-figure contributions from business organizations and corporations.

Television attack ads may be the opposition's only hope of defeating the proposal, Czuba said.

“There’s a window of opportunity," he said, "but what they really have to do is take people who are leaning toward the proposal and give them a really good reason not to support it.”

While 57 of voters said they were likely to vote for the measure, only 43 percent said they "strongly" support it. The other 14 percent who "somewhat" support the measure could still be persuadable, Czuba said.

"We're certainly not at a point where we think this is a done deal," said Scott Greenlee, who heads the opposition campaign. "We're pleased a number of folks have come to the table late and allowed us to get our messaging out to voters who are undecided or who are maybe decided but learning new information."

The pro-legalization campaign is "trying not to put too much stock into the polls," said spokesman Josh Hovey. "The opposition's advertising is only just started, and I'm assuming things will tighten up quite a bit."

But the consistency of recent polling suggests "the over-the-top hyperbole and blatant scare tactics" used to defeat the proposal aren't working, Hovey said.

A television attack ad that began airing last week warns that legalizing marijuana would allow for the sale of ice creams, cookies and candies with unlimited potency "making our way into our schools and playgrounds, putting the lives of our children and grandchildren at stake." The ad features a father whose 16-year-old son died in a marijuana-related car crash.

The ad makes "completely false" and "blatantly misleading" claims, said Hovey, who noted the initiative would allow the state to create rules limiting the potency of edible products, prohibit candies shaped like gummy bears that might appeal to kids and require the amount of active drug to be listed on product labels.

But potency limits should have been written directly into the law, Greenlee argued.

"What (the Department of Licensing and Regulatory Affairs) is going to do in the future we have no control over," he said. "They are going to have the opportunity to approve products that have 99 percent potency. We know that's what the marijuana industry will push for.

The proposal would allow for adults over the age of 21 to possess up to 2.5 ounces of marijuana. It would not authorize driving while under the influence of marijuana, which is already illegal, but critics fear it could lead to higher rates if the drug is more easily available.

The Coalition to Regulate Marijuana Like Alcohol began running television ads in recent days, Hovey said. One ad that began online features a retired state police trooper suggesting prohibition has “clogged the courts with pointless marijuana arrests” and forced law enforcement to spend time on cases that do not make the state safer.

Smarter Approaches to Marijuana, a national group that fights recreational legalization, has kicked in more than $1 million in cash and in-kind contributions for the opposition campaign. Michigan Energy First, a nonprofit led by DTE Energy's director of state government affairs, recently contributed $250,000.

The Dow Chemical Corp. of Midland donated $100,000 over the weekend. The opposition group has also reported late contributions of $50,000 each from ITC Holdings of Novi, Business Leaders for Michigan and Haworth Inc. of Holland.

Businesses "understand this is going to be a disaster for Michigan's economy," Greenlee said, pointing to company fears that marijuana residue, which stays in a user's system for weeks, could lead to more drug test failures and firings, limiting the workforce pool.

Some arguments from business groups appear to be "completely misguided," Hovey argued. "Proposal 1 protects business' rights to maintain their existing drug-free workplace policies."

The president of the National Business League, a black business group, is expected to endorse the legalization proposal on Wednesday. The Detroit NAACP came out against the measure last week.

Healthy and Productive Michigan spent more than $446,000 between July 21 and Oct. 21 and ended the period with nearly $700,000 in cash reserves.

The pro-legalization campaign spent roughly $399,000 during the same time and ended the reporting period with $151,000 in the bank. But it has also reported a series of late contributions from national advocacy groups, including the New Approach PAC, which donated more than $954,000 over the weekend. The Marijuana Policy Project has spent more than $554,000 on the initiative.

"We're matching them dollar-for-dollar, gross (television) rating point for gross rating point," Hovey said.

joosting@detroitnews.com

(517) 371-3662

Twitter: @jonathanoosting

Proposal 1

An Oct. 25-27 poll of 600 likely Michigan voters asked about Proposal 1, the ballot measure that would legalize the private, recreational use of marijuana:

Support 57%

Oppose 40.2%

Undecided 2.8%

Note: Margin of error is plus-minus 4 percentage points.

Source: Glengariff Group