In Florida, a measure to approve medicinal use of cannabis was close but ultimately did not pass Tuesday. The measure needed 60 percent voter approval but garnered 58 percent.
The midterm results bring the tally to four states and the District of Columbia that have approved cannabis for recreational use. Twenty-three states have approved it for medicinal purposes. Now with the foundation for legal use established in more states, entrepreneurs are hoping to replicate business opportunities as seen in Colorado and Washington state.
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The approved marijuana measures also will mean more job creation and added tax revenue, as Oregon and Alaska will be able to regulate and tax marijuana like they do alcohol, according to the Marijuana Policy Project, which works to reduce or cut penalties for medical and nonmedical use of cannabis.
"The results are particularly encouraging, since voter turnout during a midterm election is typically smaller, older and more conservative," Rob Kampia, the project's executive director, said in a statement. "Clearly, support for ending marijuana prohibition spans the political and ideological spectrums."
And Tuesday's vote was far from the final say on marijuana legalization.
"Proposals to regulate marijuana like alcohol are headed for the ballots in at least five states in 2016, and they're being considered in legislatures around the country," Kampia said. "This year's election was a large step forward, but the 2016 election will be a huge leap toward ending marijuana prohibition in this country once and for all."
America's legal wholesale and retail cannabis industry already reached $1.5 billion in 2013, according to the ArcView Group, which invests in cannabis businesses and collects related data. The sector is forecast to grow to $2.6 billion by this year's end, and to $10.2 billion by 2018.
In Colorado alone, the cannabis market is forecast to more than double to $801.9 million this year from $347.2 million in 2013, according to ArcView. In Washington state, where recreational and medicinal uses are allowed, the marijuana sector is anticipated to grow to $316.2 million this year from $63.4 million in 2013.
In California, where medicinal use is allowed and efforts are underway to legalize recreational use in 2016, the market is expected to grow to $1.1 billion this year from $980.2 million, according to ArcView.
And such big state market sizes for cannabis could translate to lots of revenue and jobs.
In Colorado, for example, the state has brought in $37 million in taxes for both retail and medicinal marijuana from January through August this year, the latest figures available from the Colorado Department of Revenue. Plus more than 3,500 jobs have been created through the state's cannabis industry from the beginning of 2013 through the first quarter of this year, according to recent data from the Colorado Department of Labor and Employment.
Looking ahead, other states may move toward legalization once they see how much revenue can be collected from cannabis businesses, said Kim Rueben, senior research associate at the Urban Institute's Tax Policy Center. "If you look at a state like Alaska, their oil and tax revenues are down, so they have limits. Money is a major influence for why they are [looking to] legalize," Rueben said earlier this week.