PLAINVILLE - Plainridge Racecourse will bid to become a casino if casinos are the only venues in Massachusetts that are allowed slot machines, track President Gary Piontkowski said Monday.

Gov. Deval Patrick on Monday proposed licensing three full-scale casinos through a competitive bid process open to Indian tribes and casino companies. Southeastern Massachusetts, Western Massachusetts and Greater Boston would each get one casino.

For the first time, Plainridge officials say they're prepared to turn their harness horse track into a casino.

"The partners here have already voted (Monday) and we will bid on a casino," Piontkowski said.

Plainridge and Massachusetts' other racetracks have long eyed slot machines because they are losing business to out-of-state competitors which have them. However, former Gov. Mitt Romney and the Massachusetts House of Representatives regularly opposed slots.

The Legislature must approve expanding gaming. Plainridge is ready to ante up in whatever game emerges from the Beacon Hill debate.

"We will be whatever the Legislature wants us to be," Piontkowski said. "If it wants us to be a racino, that's fine. If it wants us to be a racetrack with slots, that's fine.

"If they want us to be a casino, that's fine."

"We think we have the best location at (Interstate) 495 and (Route) 1. We think Plainville is the ideal spot," Piontkowski said.

"Would we have liked it to be just the racetracks? Of course. That's OK. We're big boys."

Piontkowski called having three casinos, and no slots at the tracks, "purely speculation."

"I haven't even thought about the possibility of us not being in gaming. That's our business," he said.

Piontkowski said Plainridge has "the most experience of anyone in the state" to run a casino.

And, situated on 91 acres, "I don't think anybody could top us to say they have a better location in the state," he said. The Mashpee Wampanoag tribe has proposed building a $1 million casino on land it owns down I-495 in Middleboro.

"Let them bid," Piontkowski said.

"It's a fair proposition for everybody. Whatever the Mashpees do, the Mashpees do. Whatever Middleboro does, Middleboro does."

Piontkowski called Patrick's plan "very heartening."

"We're thrilled that a governor in Massachusetts has come out to expand the business we're in, to expand the gaming," Piontkowski said.

State Sen. Scott Brown, R-Wrentham, said allowing slot machines at race tracks like Plainridge Racecourse in Plainville would have been a better way to go because the track is already set up for slot machines.

He said the track could have its slot machine operation running and producing revenue for the state in three months, rather than the three years it will take for casinos to open.

Furthermore, he said about 50 percent of the revenue from slot machines would go the state, as opposed to 18 or 19 percent for casinos.

Still, Brown said Plainridge is in a good position to compete for a casino license.

He said the track already has the infrastructure in place with routes 1 and 1A along with Interstates 495 and 95.

The track also has investors lined up who have experience in a casino in New Mexico, he said.

"I think it's encouraging for this area," he said.

Staff Writer Jim Hand contributed to this report.

MICHAEL GELBWASSER can be reached at 508-236-0439 or at mgelbwasser@thesunchronicle.com.