A crowd big enough to fill a pro sports arena is expected here Saturday for that quintessential rural New England event, the Town Meeting.

Generally no more than a few hundred people attend such meetings, even on hot issues, but officials are preparing for three-quarters of this town of 20,000 to show up. Residents will be marking paper ballots on whether to accept a deal with an Indian tribe to build a USD 1 billion casino.

„It’s direct democracy, how could you beat it?“ said Jessie Powell, an opponent of the plan. „It allows people to have a voice in how their town is governed.“

There’s no place to hold a crowd that big in this rural but growing community about 45 miles south of Boston, so the meeting will look more like a college commencement — held on athletic fields behind the high school.

There will be no parking allowed nearby. Buses will shuttle voters to and from various locations around town. People are being advised to bring binoculars, folding chairs, and snacks. The meeting opens at 11 a.m., but residents are being urged to arrive up to three hours early.

The issue is whether to sign a deal with the recently recognized Mashpee Wampanoag tribe to host a casino — should casino gaming become legal in Massachusetts.

„This will alter the town,“ Powell said during lunch at Nathan’s Place on North Main Street. She has been going to her neighbors‘ houses to try to persuade them to vote no.

Town officials need Town Meeting approval of a contract with the tribe that would pay Middleborough USD 11 million per year, among other benefits, in exchange for hosting a resort casino and supporting the tribe’s efforts to win state approval.

Gov. Deval Patrick has not said if he would support legalizing casino gaming in Massachusetts, and state Treasurer Tim Cahill has said Middleborough’s vote is in some ways „a hypothetical exercise.“ He also said he didn’t think the town would get a big enough cut under the current deal.

Tribe spokeswoman Amy Lambiaso said they are optimistic the residents will support the proposal.

„Middleborough is the ideal location because of the tribe’s historical roots there,“ she said, declining to specify whether the tribe would give up on Middleborough if they lose the vote. „We’ll continue talking to town leaders.“

Even without state approval, the tribe by virtue of being federally recognized could operate bingo parlors in Middleborough because it’s within 50 miles of its tribal home on Cape Cod.

So some supporters, like Nathan’s Place manager Sue Glendye, will vote for the agreement, figuring the town should cash in while it can.

„They’re going to build it whether the town wants it or not,“ Glendye said. „I think the Wampanoags are being very generous, actually. They’re make a very good deal for the town. The town needs it.“

Town Meetings date back to the creation of Massachusetts towns in the 1630s, said Peter Drummey, librarian at the Massachusetts Historical Society. The sessions typically were limited to a handful of male landowners who made decisions for the village.

Saturday’s meeting is shaping up to be one for the history books.

Roger Brunelle, the town’s information technology director, is handling logistics and is responsible for everything from portable toilets to sound checks on the field for the meeting. Total cost to the town: $ 100,000.

He likened security and logistics to a visit by a head of state.

„I’ve never had a presidential visit, but I’ve seen them on TV,“ he said. „They weld down manhole covers. We don’t have manhole covers.“