A ballot measure allowing medical marijuana was too close to call. Unofficial returns Nov. 2 showed Proposition 203 trailing by a narrow margin.

If voters say yes, the operators of the first medical marijuana dispensary say they can open the doors a day after the election.

Municipalities fear that without restrictions, the roughly 120 marijuana dispensaries that would be allowed to open if Proposition 203 passes could cluster in cities or be placed near churches, parks, community centers and even drug-treatment facilities.