By Kim Palmer
CLEVELAND (Reuters) - Ohio voters were deciding on Tuesday whether to become the first U.S. Midwestern state to legalize the recreational use of marijuana, although a rival ballot measure could kill the law before it takes effect.
Issue 3 would add an amendment to the state constitution that legalizes both the personal and medical use of marijuana for those over 21 years old.
If it passes, Ohio would become the fifth and most populous state to legalize the recreational usage of marijuana, following Alaska, Colorado, Washington and Oregon, as well as the District of Columbia. About two dozen states allow its use for medical reasons.
Recent opinion polls showed voters split on the issue.
Ohio is considered a political bellwether, with the candidate who wins the state usually winning the presidency. A victory for recreational marijuana in Ohio is expected to change the national conversation on legalization, said Gary Daniels of the Ohio American Civil Liberties Union.
Seven other states are expected to vote on recreational marijuana legalization next year.
Polls close through most of the state at 7:30 p.m. (0030 GMT on Wednesday). But polls will stay open an extra 90 minutes in Cincinnati after voters complained of problems with electronic poll books, as well as not having enough provisional ballots.
Ian James, executive director of Responsible Ohio, a political action group that brought the issue to the ballot, said the vote could be "very close" and he did not expect to know results until 11 p.m. or later.
Issue 3 also grants exclusive rights for commercial marijuana growth and distribution to 10 facilities across the state. Those facilities are owned by investors in the legalization movement.
Critics say that creates a monopoly, and responded with a rival ballot measure called Issue 2. That would nullify legalization if it creates "an economic monopoly or special privilege" for a private entity.
NORML has endorsed the legalization measure, although with "some hesitancy" because of the limited number of growing sites, said Danielle Keane, political director for NORML, a legalization advocacy group.
Ohio State University constitutional law professor Daniel Tokaji said he believed the legalization measure would fail because of the word "monopoly" in the ballot language.
Nikhil Bhatnagar, an anesthesiologist from suburban Cleveland, said he and his wife, a pediatric dentist, voted against Issue 3.
"We believe that the increase in tax revenue would be lost in the increased healthcare costs," Bhatnagar said.
(Reporting by Kim Palmer; Editing by Mary Wisniewski and Peter Cooney)