When the third richest man in America speaks, you listen. And when he happens to be a gambling mogul visiting his home state of Massachusetts as the governor's special guest, you listen closely.

Sheldon Adelson - #3 on the Forbes 400 - made an appearance in Boston last month at the governor's seven-hour casino jamboree. It was the first big attempt by Gov. Patrick to force the hand of his rival, anti-casino House Speaker Sal DiMasi.

Adelson, who owns the storied Sands in Las Vegas as well as casinos in Macao, wants to get one of the casino licenses the governor is pushing the Legislature to approve, and use it to build a gambling emporium in Marlboro, about 45 minutes up I-495 from here.

Chatting with reporters outside the Statehouse, the Dorchester-born Adelson offered the sort of boastful bravado you'd expect from a man who's put everyone but Bill Gates and Warren Buffett in his rear-view mirror.

"We've got the Pats, we've got the Sox, we've got the Celtics, and we've got Adelson," the 74-year-old said at least three times, according to The Globe. "They're champions at what they do. We're champions at what we do." And that, of course, is the big concern.

There's no question that casino developers are champions at what they do, which is maximize their profits. Providing cash-starved states like Massachusetts with a steady tax revenue stream is only a side effect - and, as Sen. Susan Tucker of Andover said, it represents "the most regressive form of taxation ever invented by mankind."

Indeed, Adelson and Patrick make quite the odd couple.

The Democratic governor ran as a liberal reformer who was going to blow open Beacon Hill backrooms and spend big money investing in the state's infrastructure and social services.

That's quite a contrast with Adelson, a Republican donor who spreads his money around.

Adelson has made millions of dollars in political contributions, the vast majority of it to Republican candidates and causes. (He hasn't given to a Democrat in nearly 10 years.) Rudy Giuliani has used Adelson's private jet to travel to campaign events.

In Las Vegas, Adelson is known for fighting legal battles against the powerful Culinary Workers Union, the Vegas tourist authority, and even the electric company, according to The New York Times. His suit against John L. Smith, a top columnist for the Las Vegas Review-Journal, drove Smith into bankruptcy.

Then again, Patrick is a product of executive boardrooms, comfortable with big money and corporate power. "Democrats, I think, have got to get over their discomfort with the private sector," he chided his opponents at a Democratic gubernatorial debate in 2006.

And, of course, Adelson is only the wealthiest of the many developers hoping to carve out a slice of the lucrative gambling pie, should the Legislature act on Patrick's proposal.

The governor's latest tactic is to make legislators an offer they can't refuse, by including the $800 million in casino licensing revenue in his soon-to-be-released budget proposal. Indeed, gambling has become the Patrick Administration's top priority.

At Tuesday night's meeting about the proposed South Coast train line, Norton's Ed Kelley asked Kristina Egan, Patrick's point person on the train project, whether it was being driven in part by the casino plan, since one of the proposed routes would go through Middleboro, where the Wamponoag tribe wants to build their own casino. Egan replied that the governor wants to "make sure the train proposal and the casino proposal are coordinated at some level."

The Bay State is not an isolated case. Down in Rhode Island, where legislators are grappling with a $450 million budget deficit, the owners of Twin River - which is not a casino officially, but sure looks like one after a glitzy makeover - are asking the state to allow gambling 24 hours a day, saying it could bring the Ocean State up to $16.5 million more in annual revenue.

Last year, The Globe's Jenna Russell reports, Twin River sent even more money to Rhode Island's state treasury than Foxwoods sent to Connecticut's - which raises the question of why the governor is so set on having resort casinos as opposed to expanding gambling at tracks like Plainridge in Plainville.

But Russell also related a story that reminds us of where all that money comes from. Scott Pelman, a marketing executive from Dedham, told Russell that he was bored at home, so he decided to visit Twin River. He promptly lost $400.

"I'm disappointed in myself for coming down here," Pelman told Russell. "I had the day off, and I could have done anything else."

The question now is which voice will ring more loudly in our legislators' ears: Scott Pelman's or Sheldon Adelson's?

TED NESI is a Sun Chronicle staff writer. His column appears on Fridays. He can be reached at tnesi@thesunchronicle.com.