Meanwhile, ballot measures in Massachusetts and Arizona involving the lower minimum wage for workers who primarily rely on tips were overwhelmingly rejected.

Here's a look at how those and other employment-related ballot measures fared across the country in Tuesday's election.

MINIMUM WAGE HIKES

Nearly 58% of Missourians voted in favor of the minimum wage increase, which will make Missouri the eighth U.S. state with a minimum wage of $15 or more. The proposal in Alaska appeared likely to pass, with a 56.5% approval rate as of Wednesday morning, though not all votes had been tallied. The federal minimum wage of $7.25 per hour has not increased since 2009, and about 30 states have set their floor higher.

Both states' proposals also include paid sick leave programs, which have already been adopted in 18 states and Washington, D.C. Voters in Nebraska also approved a paid sick leave program by a margin of nearly three to one.

A proposal to raise California's minimum wage to $18 per hour, which would be the highest in the country, appeared likely to fail on Wednesday morning. According to state results, 52% of voters had disapproved of the proposal with many precincts only partially reporting their tallies.

Alaska's minimum wage measure also includes a provision that would ban mandatory meetings to discourage unionizing, known as captive audience meetings. At least nine Democratic-led states including New York, California, and Minnesota have banned the meetings or prohibited employers from disciplining workers who do not attend. Captive audience meetings are legal under federal labor law and have been a fixture of employers' responses to union campaigns for decades.

TIPPED MINIMUM WAGE

A proposal known as Question 5 asking voters to eliminate Massachusetts' $6.75 per hour minimum wage for tipped workers failed by a nearly two-to-one margin, after a coalition of industry groups, workers and Democratic state officials urged voters to reject it.

Question 5 would have gradually raised the tipped minimum wage until it matched the standard minimum - currently $15 per hour - in 2029. Supporters including advocacy group One Fair Wage have said that pay for tipped workers can be inconsistent and unpredictable and that relying on tips makes workers more vulnerable to harassment.

But opponents of the proposal said it would lower the pay of servers and other workers who rely on tips while forcing restaurants and other businesses to raise prices or close their doors.

In Arizona, meanwhile, voters resoundingly rejected a ballot measure that would have enshrined a lower tipped minimum wage in the state constitution, by a margin of nearly three to one.

The proposal, the first of its kind, would have allowed for tipped workers to be paid 25% less than the state's standard minimum wage, which will rise to $14.70 per hour on Jan. 1. Currently, Arizona wage law sets a tipped minimum wage of $12.35 per hour. The proposal would have initially lowered that to about $11 while tying it to future minimum wage increases.

CANNABIS

Voters in Oregon made the state at least the seventh to require cannabis businesses to adopt "labor peace agreements" requiring them to remain neutral in union campaigns in order to receive or renew state licenses, by a 55%-45% vote, Edison projected. The legal cannabis industry is rapidly unionizing, and the passage of the proposal will likely make it easier for workers in Oregon to join unions.