Since July, gamblers have plunked $511 million into Maryland’s slot machines, which now number 6,831 across the state. That amount already exceeds the state’s projection of $498 million in revenue, with a full month left to go until the end of the current fiscal year.

The better-than-predicted performance comes as welcome news in a state where lottery sales have slipped by about 2 percent and will finish with a decline for the first time in 16 years.

Stephen Martino, head of the Lottery and Gaming Control Agency, said in a statement that he was pleased. “While we have seen a slight decrease in lottery revenues, the launch of table games and the opening of two additional casinos has increased the overall benefit to the state, particularly to the Education Trust Fund which supports pre-K-12 public education.”

Slots have pumped $250 million into the fund in fiscal 2013, surpassing estimates.

Live-action table games — approved by Maryland voters in November but only recently added to Hollywood Casino Perryville, Maryland Live Casino and the new Rocky Gap Casino Resort — have brought in almost $31 million in gross gambling revenue, nearly $20 million of it last month.

Most of that money came from Maryland Live, where 122 live-action tables generated more than $17.5 million in the first full month of operation. The casino, which opened a year ago Thursday at Arundel Mills, collected nearly $37.5 million from its 4,319 slot machines.

With a total haul of $55 million — the most ever in Maryland — the suburban property generated more than $1.7 million per day last month. More than half of that was collected for state and local taxes.

“The state has been a wonderful partner in achieving all of our success and our goals,” said Robert J. Norton, Maryland Live’s president and general manager, adding, “Understand that they are the lion’s share of the partnership.”

Since opening last year, Maryland Live — one of the country’s largest commercial casinos — has paid nearly $300 million in gambling taxes.

Look for more in the coming year. Norton said the $55 million in a month was hardly unexpected, and that Maryland Live is adding a two-story, 50-tables-plus poker room this summer.

“I think there’s room for growth,” he said of the property’s revenue, which is among the highest on the East Coast.

Hollywood Casino Perryville reported nearly $7 million in slots revenue and $1.6 million from its modest table-games operation, including the state’s only poker room.

The Casino at Ocean Downs collected nearly $4.8 from its 800 slot machines; it doesn’t plan to add table games until after summer.

The new Rocky Gap Casino Resort, which opened May 22, generated just under $800,000 in its first 10 days of operation. The western Maryland casino has 554 slots and 10 gaming tables.