If you bet the over last month on Maryland’s gross gambling revenue, then it’s time to collect.

Maryland’s four casinos raked in $71 million in August, a record for the state’s rapidly expanding gambling sector. More than $28 million was sent to the state’s Education Trust Fund in August.

According to State Lottery and Gaming Control Agency figures released Thursday, three-fourths of the haul came from Maryland Live. The ­airport-terminal-size gambling hall at Arundel Mills — the state’s largest casino — brought in more than $53 million in gross revenue in August, the fourth consecutive month that it has cleared more than $50 million.

Most of the pre­tax windfall came from Maryland Live’s slot machines ($35.5 million at 4,339 terminals) and live-action table games ($17.4 million at 122 tables offering blackjack, baccarat, craps and other games). But a new poker room, which opened Aug. 28 with considerable buzz and long lines, also added to the casino’s bankroll, pulling in more than $350,000 in its first 31 / 2 days of business.

Maryland Live officials have said they expect the split-level, 52-table card room to generate more than $1 million each month. Since opening last week, it has been one of the busiest card rooms in the country; on Wednesday night, only the Commerce Casino near Los Angeles had more tables running.

The statewide gambling haul has been increasing at a dizzying rate in the past year, particularly since November, when Maryland voters approved a dramatic expansion of casino gambling, including 24-hour operations and the addition of the Las Vegas-style table games.

Excluding Rocky Gap Casino, the small resort that opened in May in Western Maryland, year-over-year casino revenue in the state was up about 50 percent, or $22 million. Maryland Live alone was up $20.9 million in year-over-year gambling revenue.

See previous stories in an occasional series exploring the changing casino industry and gambling culture in Maryland.

Slot revenue at Maryland Live and Hollywood Casino Perryville is taxed at 67 percent. Rocky Gap and the Casino at Ocean Downs pay lower rates (50 percent and 43 percent, respectively). Hollywood, Maryland Live and Rocky Gap send 20 percent of table-game revenue to the state; Ocean Downs does not have table games.