Ohio voters have approved a measure to legalise adult recreational marijuana use. It will take effect in 30 days.
Voters supporting the new law, known as Issue 2, defied the will of the state's Republican controlled legislature.
The measure was first introduced in 2022, but was stalled by Republican lawmakers, triggering a lawsuit to get legalisation on the ballot.
On Tuesday, Ohio became the 24th state in the US to legalise non-medical cannabis use.
"Marijuana is no longer a controversial issue," said Tom Haren, spokesman for the Coalition to Regulate Marijuana Like Alcohol. "Ohioans demonstrated this by passing State Issue 2 in a landslide."
The new law will allow adults over 21 to purchase and possess up to 2.5oz (70g) of cannabis and to grow up to six marijuana plants at home.
Buyers will pay a 10% tax imposed on sales going mostly toward addiction services, communities with cannabis facilities and social equity and jobs programmes.
The drug is illegal at the federal level despite a number of US states having passed laws legalising its use in some form.
Cannabis is legal for adult recreational use in 23 other states, including all west coast states and in Washington DC. It is permitted for medical use in 38 states.
The Ohio law is a citizen-initiated statute and not a constitutional amendment, which means state lawmakers have the power to easily adjust or even repeal the law.
Ohio Republicans who remain opposed to Issue 2 are already calling for changes.
"This fight is not over," Smart Approaches to Marijuana Action President Kevin Sabet said in a statement obtained by the Associated Press. He called on state legislators to remove parts of the law that enable commercial and advertising sales.
Others have voiced their concerns regarding the limits of THC, the psychoactive compound that gives marijuana users a high.
Since voters approved the law, it will be tricky political ground for Republican lawmakers looking to make tweaks without upsetting their constituents.
Ohio also voted on Tuesday to amend the state's constitution in favour of abortion rights.
