State senators voted 21-to-13 in favor of the measure early Saturday, after nearly 10 hours of debate dominated by bill opponent Republican Sen. Toni Boucher.
Democratic Gov. Dannel P. Malloy, who has said he supports the measure, is expected to sign the legislation into law.
The bill moves away from the largely criticized precedent set in California, proposing a complex regulated system of cultivation, dispensing and licensing.
The Connecticut bill outlines specific diseases that would be treated under the drug. It requires a recommendation from an individual's physician and establishes a system of licensing for patients, caregivers and growers.
