PORTLAND — Local community and business leaders are throwing their support behind a ballot question asking voters to approve a casino in Maine’s second-largest city, while an animal rights group is opposing a separate question calling for racetrack casinos in southern and eastern Maine.

A casino in downtown Lewiston will generate short- and long-term jobs, generate revenues and revive the downtown area, supporters say. Lewiston Mayor Larry Gilbert said he doesn’t know of any local organized opposition to Question 3 on the Nov. 8 ballot asking voters statewide if they want to allow a casino in Lewiston.

Great Falls Recreation and Redevelopment LLC is proposing to spend more than $100 million to build a casino with slot machines and table games in a sprawling textile mill called Bates Mill No. 5 that has been idle for years. Backers have said it would employ up to 800 workers during construction and 500 or so employees after it opens in 2013.

The Lewiston City Council and the Lewiston-Auburn Economic Growth Council are endorsing the project, and most people locally don’t buy the argument from critics that casinos suck money out of the economy and don’t represent economic development, Gilbert said.

“Where else in Maine have we seen job creation such as this?” he said.

A group of Lewiston-area political and business leaders are holding a news conference on Tuesday to express their support for the casino. At that time, supporters are planning to announce the creation of a political action committee in support of the project.

Dennis Bailey, executive director of the Casinos No!, said community leaders are fooling themselves if they think a casino will help revitalize the city.

“There isn’t a town in America where a casino has improved a downtown or revived a downtown or brought business downtown,” Bailey said. “It doesn’t work that way. In fact, it does the opposite. It drives business away.”

Meanwhile, an animal rights organization that forced an unsuccessful ballot referendum in 2004 seeking to outlaw the use of bait, traps or dogs to hunt bears is urging voters to oppose Question 2 on the Nov. 8 ballot, which seeks approval for two new harness racing tracks in Maine.

Developers are proposing to build a $120 million racetrack casino, or “racino,” with a hotel and entertainment complex called Biddeford Downs in Biddeford, which they say will create 800 construction jobs and 500 full-time jobs. If approved, the facility is projected to open in 2013. The Passamaquoddy Tribe would have the right to build a separate racino in eastern Maine, presumably in Calais, but the tribe has not unveiled specific plans.

The head of Maine Friends of Animals said in a statement that harness racing is a cruel sport that abuses horses. Robert Fisk Jr. said many harness racing horses are kept in inhumane conditions, are drugged to enhance their performance and are discarded after their race days are over.

Don Marean, a horse farm owner from Hollis who has been involved in the harness racing industry for decades, said Fisk’s assertions are untrue. Marean supports the Biddeford Downs proposal because it would provide a boost to the harness racing industry, he said.

“I’ve been in this industry for 30 years,” Marean said. “Harness racing people take real good care of their horses.”