BOSTON — A daylong hearing on casino gambling at the Massachusetts State House this week drew a huge crowd of red-shirted union workers and some of the world’s wealthiest casino executives who flew in for the occasion.

But missing from the scene were the Wampanoag Tribe of Gay Head (Aquinnah) and its sister tribe in Mashpee.

Gov. Deval Patrick wants to license three casinos in the state, one in southeastern Massachusetts, one in the Boston area and another in the western part of the state. He faces an uphill fight in the state legislature, especially on the House side, where Speaker Salvatore F. DiMasi is strongly opposed to casino gambling.

Nevertheless, the governor’s pitch to bring casinos to the commonwealth has ignited a feisty public debate that is fraught with complicated politics. And the stakes are high — Governor Patrick estimates that commercial casinos would generate more than $400 million in annual tax revenue and some $2 billion in economic activity in the commonwealth.

Money was a principal theme at the Monday hearing in the Gardner Auditorium, sponsored by Joint Committee on Bonding and Capital Expenditures, attended by nearly 500 people and lasting for seven hours. Union workers want casino jobs, Governor Patrick has set his sights on windfall revenues and prospective casino operators want profits.

“The hearing was totally orchestrated by groups in the state house that want to see this happen,” said Cape and Islands Sen. Robert O’Leary following the hearing. Mr. O’Leary, a staunch opponent of casino gambling, testified against the bill. “This is not a good deal for the state. I think the liabilities have been understated and the advantages overstated,” he said at the hearing.

And while no one from either the Aquinnah or Mashpee Wampanoags testified, the role of the tribes in any future casino venture was a topic for discussion.

The Mashpee Wampanoags, who just recently received federal recognition, want to build a casino on a large piece of land held in federal trust in Middleboro.

Sen. Mark Montigny, a Democrat from New Bedford who is co-chairman of the joint committee on bonding, singled out the Mashpee Wampanoags for harsh criticism for their investment partnership with Sol Kerzner and Len Wolman, developers of the Connecticut casino Mohegan Sun who reportedly will take in more than $675 million through the year 2014 in an extraordinarily lucrative contract deal. “The tribal chairman says he doesn’t know about deals made by his predecessors and that a new deal has been made. I would say to him, get back the $300 million or distribute it to the 1,700 tribal members and let’s start at the beginning with complete transparency,” Mr. Montigny said.

The Aquinnah Wampanoags have formed a partnership with Seneca Nation, an upstate New York Tribe that runs several successful casino ventures, and are hoping for the second time in more than 15 years to land a license for a casino, if Governor Patrick’s bill clears the legislature.

The Mashpee tribe believes it can use its sovereign status to build a casino with little or no state oversight under the federal Indian Gaming Regulatory Act.

Daniel O’Connell, state Secretary of Housing and Economic Development, who took special note of this during the hearing, also noted that the Aquinnah Wampanoags are in a markedly different position when it comes to their sovereign status. In a settlement agreement signed with the town in 1986 and later ratified by the state and federal governments, the Aquinnah Wampanoags agreed to abide by state and local zoning laws on land use projects. The Wampanoags challenged the agreement and lost in a landmark court case that was argued all the way to the state Supreme Judicial Court. In 2004 the state’s highest court ruled that the settlement agreement trumped the doctrine of sovereign immunity, at least on the subject of land use. The tribe chose not to appeal in federal court.

Most of the testimony on Monday came down in favor of the casino bill. About half crowd was hotel union workers flown in from Las Vegas, Detroit and Atlantic City casinos who wore red T-shirts that read “Casinos + Unions” and “Good Jobs.” The League of Women Voters joined Senator O’Leary in the minority expression against gambling.

But as Senator O’Leary said in his testimony, “Whatever deal is on the table today will change tomorrow.”

More hearings are expected in the weeks and months ahead.