RICHMOND — With Virginia Gov. Glenn Youngkin’s plan to build a $2 billion arena in Alexandria for the Washington Capitals and Wizards in jeopardy, three political and business figures have been pitching an unlikely Hail Mary: an idea to pair the sports arena with a new casino in Fairfax County.

Instead of building the arena in Potomac Yard with taxpayer-backed bonds, their plan calls for putting it in the Tysons area alongside the casino, with tax revenue generated by gambling used to guarantee the arena bonds.

The idea has been flatly rejected by Youngkin (R) and the teams’ owner, Monumental Sports & Entertainment, who still hope that their original plan to build the arena in Potomac Yard will overcome setbacks in the General Assembly. And the casino idea itself has been unpopular in Northern Virginia: Amid vocal opposition from residents and local officials, the General Assembly last month kicked a bill calling for a casino in Tysons to next year’s legislative session.

But the three who have pitched the casino-arena idea — Senate Majority Leader Scott A. Surovell (D-Fairfax); Christopher Clemente, chief executive of Comstock, the company seeking to build the casino; and Ben Tribbett, a prominent Fairfax political and business consultant who counts Surovell, Comstock and the arena’s chief opponent, Sen. L. Louise Lucas (D-Portsmouth), as clients — say it could revive both projects and leave Lucas, the Senate Finance and Appropriations Committee chairwoman and the arena’s self-described one-woman “roadblock,” satisfied that the sports complex would not put the state’s finances at risk.

Lucas, often an ally to Virginia’s gambling industry, said in an interview Friday night that she had not heard of linking the arena and casino until Surovell called her earlier in the day from Poland, where he has been vacationing.

“I didn’t know anything about it,” she said. “That was some plan that Scott had come up with.” She said she did not know enough about the idea to offer an opinion.

Their efforts come as backers of the original deal mount an 11th-hour scramble to rescue a project that much of Richmond has left for dead. Youngkin continues to press for what would be a legacy-defining economic development coup and is expected to try to revive the plan in a bill or budget amendment when the General Assembly returns April 17. The project’s real estate developer JBG Smith, meanwhile, sought to woo Democrats by announcing on Friday that it would double its commitment to preserve affordable housing near the site if the arena is built on land owned in part by the company.

Surovell said Friday that he pitched the casino idea a little over a week ago to Monica Dixon, Monumental’s president of external affairs. Dixon immediately shot him down, Surovell said, so he dropped it.

“As this [arena] project has imploded in the last three weeks … one of the concepts that I floated was the possibility of merging the arena with a Northern Virginia casino and using the casino tax revenue to backstop the bonds instead of the state’s general fund,” Surovell said. “Monumental was not a fan, and that was the end of the conversation.”

Dixon confirmed that stance in an email. “At no time, have we ever or would we ever consider operating alongside a casino, period,” Dixon wrote. “Our proposal in Alexandria at Potomac Yard provides our fans, players, employees and the people of this region the best opportunity for winning teams and a great economic impact. While we are disappointed in how this has played out, we hope our proposal will get a fair hearing.”

But Clemente and Tribbett continued shopping the idea last week. Clemente pitched it directly to Monumental owner Ted Leonsis in a phone call Wednesday, a Monumental spokesman said, and again later that day to Matt Kelly, chief executive of JBG Smith, which would build the arena. Tribbett also discussed it Thursday with Dixon, the Monumental spokesman said.

“The idea was, ‘Let’s kill the arena in Potomac Yard and we can bring it back to life, paired with a casino, and the casino will help pay for the arena, and the arena will help disenfranchise the referendum voters,” Kelly said Saturday, meaning the casino plan might be structured in a way to avoid the local referendum required of other casinos. “But it was ill-conceived and naive from the beginning because nobody ever came to Monumental and said, ‘Do you want to do this?’ — not until this week. It’s amateurish.”

Tribbett has a dual role, advising Lucas — who has single-handedly blocked the arena project so far, killing two stand-alone bills without giving them hearings and blocking negotiators from authorizing the arena through the budget bill — while also representing Clemente’s company and his bid for a casino. Tribbett said there was nothing wrong with representing clients with opposite views on an issue.

“When we have a client that is putting a stadium bill forward and we have another who is the lead opposition, is that awkward?” he asked, referring to Surovell and Lucas, respectively. “That’s politics.”

In a text message, Clemente said the idea of marrying the arena and the casino “was brought to us by multiple legislators during session. … Combining the two would potentially enhance financing options for the arena, making [it] better for Virginia taxpayers which I believe is why legislators brought this up to us to begin with.”

Kelly confirmed that he contacted Clemente, whom he had met in Richmond in January while they were promoting their respective arena and casino plans. Kelly said he wanted to pick Clemente’s brain about ways to win over Lucas, whose campaign received $100,000 from Clemente days before the fall election. Kelly said what he got instead was a confusing pitch.

“I had actually reached out to him because we were trying to figure out how we could get a fair hearing with Louise,” Kelly said. “He asked me, ‘Would you be interested in putting your arena next to my casino in Tysons Corner?’ I said, ‘I don’t understand why you’re even asking me that question.’ We started talking then about his whole effort around the casino and all that stuff, and he said … ‘Do you think they would want a casino in Potomac Yard?’

“And I said, ‘Hell, no. The people there would never allow a casino, and Virginia Tech’” — which is building a graduate campus next door — “‘wouldn’t want it, and we wouldn’t want that. That’s not our business.’ But I thought it was really, really strange.”

Meanwhile, Leonsis called Youngkin on Thursday to voice disgust with what he saw as pressure to link his proposed arena to the casino, according to three people familiar with the conversation who spoke on the condition of anonymity to share a private discussion.

Youngkin spokesman Rob Damschen said in an email: “The Governor expressed immediately and directly that he had no interest in the arena-casino deal proposed to Monumental.”

Surovell said Friday he was surprised to hear that the arena-casino proposal had made its way to the governor. He said the notion was only in the “conceptual” stage, something he thought was worth running by Monumental to see whether it was even a possibility.

Prominent Northern Virginia Democrats said they were caught off guard by the idea. Alexandria Mayor Justin M. Wilson (D), who supports the original arena plan, called Surovell overseas Friday after catching wind of the talk of building the facility in Fairfax, Surovell said. “The city’s angry about it,” Surovell said.

Wilson declined to share details about his conversation with Surovell but said any effort to pair a Virginia arena with a Tysons casino “sounds far-fetched, to be perfectly honest.” He contrasted the backroom pitches with what he characterized as a lengthy and public-facing process to engage his city’s residents on the Potomac Yard proposal.

“From the minute we had a framework proposal for consideration, we brought this out to the community,” he said. The push for a Tysons alternative “does not sound like a transparent process,” he added.

Fairfax County Board of Supervisors Chairman Jeffrey C. McKay (D), who had expressed skepticism about a casino in Tysons, said no one had contacted his office or anyone else in county government about that possibility — which he called “profoundly disappointing.”

“I wouldn’t even put it in the category of Hail Mary,” said Del. Mark D. Sickles (D-Fairfax), vice chairman of the House Appropriations Committee, who said he had heard rumors that the two projects could be linked but had not put any stock in them given that the Fairfax supervisors had not asked for a casino — something that has been a prerequisite for all of the state’s other casinos. “I would say bad dream.”

Armus reported from Washington.