Backers of a constitutional amendment to allow Florida patients to use marijuana for medical purposes say they will turn in enough signatures to qualify for the fall ballot by next week.

Supporters of the measure have until Feb. 1 to submit just over 683,000 valid signatures of registered voters. Realistically, backers are shooting for about 1 million signatures, to account for any deemed invalid; organizers say they will hit the million-signature mark by next week.

“As of tomorrow, we should be right at, maybe a little bit under, a million” signatures, said Ben Pollara, who runs the People United for Medical Marijuana campaign that’s spearheading the initiative. “By this time next week, we should have more than enough to give us some comfort that we should be on the ballot.”

So far, the Florida Department of Elections says the group has submitted 265,000 valid signatures. The group says it has hundreds of thousands of signatures still being processed by county elections officials.

Once the signatures are submitted and verified, Florida’s Supreme Court will rule on whether the amendment’s ballot title and summary meet legal requirements, a decision likely to come before the beginning of April (See the proposed summary language here).

And if the measure makes the ballot, organizers say poll results show they will start the fall campaign in strong position.

A Quinnipiac University poll conducted in November showed a huge majority of Florida voters, 82 percent, backed allowing adults to use marijuana for medical purposes if their doctor prescribes the drug. Just 16 percent of voters said they opposed marijuana for medical use.

The same poll showed a slim plurality — 48 percent — supported allowing adults to possess small amounts of marijuana for personal use. Forty-six percent said they opposed recreational marijuana use.

But backers are still preparing for a big fight. Pollara said his group will aim to raise at least $10 million for the fall campaign, which will share the stage with a high-profile race between Gov. Rick Scott (R) and his eventual Democratic challenger.

“We’re a big state. We have a lot of media markets. They’re going to be expensive, given the governor’s race,” Pollara said.

At present, 18 states and the District of Columbia allow patients to use marijuana for medical purposes, while two states — Colorado and Washington — allow legal purchases for non-medical use. Eleven of those states legalized marijuana for medical use through ballot initiatives.