CASPER, Wyo. (AP) - As supporters of an initiative to get medical marijuana on the ballot continue to struggle to gain signatures, infighting is threatening to make the job even more difficult.

Chris Christian stepped down as head of the Wyoming chapter of the National Organization for the Reform of Marijuana on Sunday. The former executive director sent a message to supporters on Sunday saying she believes the effort is over.

Since July, supporters of the petition have worked to collect more than 25,000 signatures of registered voters by February 8. Christian says she believes they are about 20,000 signatures short.

Christian says the effort was hurt by NORML members who wanted the measure to include recreational marijuana.

NORML Deputy Director Lee Roith says he hopes new leadership with bolster support.