LEWISTON — Downtown casino backers made good on their agreement with the city Friday, paying their final installment for an option to buy the Bates Mill No. 5 building before November’s vote.

Stavros Mendros, manager of the Great Falls Recreation and Redevelopment LLC, and partner Peter Robinson were on hand at Lewiston City Hall on Friday afternoon to write and hand over a check for $30,000 — the biggest they’ve given the city.

“I don’t know, what do you call this? The river? The flop?” Mendros said. “I don’t know the lingo. All I know is we’re all in.”

Voters in Lewiston approved an agreement a year ago, giving the casino group the option to purchase the Bates Mill building No. 5. 

Under the terms of that option the group has made two previous $10,000 payments, in June 2010 and February. The $30,000 payment was due July 31. 

A final $100,000 payment would be due on Dec. 31, 2011 — two months after the matter goes before voters at a statewide referendum. The group collected almost 75,000 signatures from registered Maine voters to qualify for the November 2011 ballot. 

Mendros said the group is now turning its attention to that statewide campaign.

“Our budget is $2 million in promotions that we are committed to, with more than $1 million on TV,” Mendros said. Ads should begin appearing in September, although Mendros said there could be some promotions planned locally around the Great Falls Balloon Festival, which begins Aug. 19.

“We want to have a big presence there because it’s part of our community,” Mendros said. “And hopefully, when we open the casino, we’ll work even more closely.”

Mendros and Robinson said the group is still in negotiations with multiple national groups interested in investing in the Lewiston casino.

“I had one offer to come in and pay this $30,000 for us, but I want to keep that separate,” Robinson said. “We paid for all of this ourselves.”

Investors include Robinson and  local anesthesiologist Ron Chicoine, New Hampshire anesthesiologist Tim Poutre and his wife, Wendy Chicoine-Poutre.

Local convenience store owner Steve Roop joined the group in February. Mendros said the group has added three other members since then: Former state legislators John Buck of Yarmouth, Ken Lindell of Belfast and former Boston police officer Peter Marrs of Monmouth.

Mendros said that investments from that group are funding the campaign so far.

“They’re helping us move it forward to the next phase,” Mendros said.

The group estimates it would return between $21 million and $30 million to state, regional and local governments and efforts each year. That money goes to a wide array of groups, including local towns and would-be competitors. As much as $4.5 million could go to local governments — Lewiston, Auburn, Androscoggin County and surrounding towns.

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