REVERE — Wynn Resorts, hoping to stomp out a potential gaming competitor in a neighboring city, poured $39,000 into a stealthy and successful last-minute campaign against Tuesday’s vote on a slots parlor, a company official confirmed on Wednesday.
The “Revere Can Do Better’’ committee was formed just seven days before the vote on a slots parlor, according to paperwork filed with the Revere Election Commission. Within that time, the Wynn-backed group paid for mailers and an automated phone call in which Mayor Brian M. Arrigo urged voters to defeat what he called a “fly-by-night’’ proposal.
“We funded that committee. We’re not hiding from it,’’ Robert DeSalvio, Wynn Boston Harbor president, said in a statement.
The Revere Can Do Better committee didn’t show its fingerprints in its public filings, however. The two-page registration it filed with the Revere Election Commission last week shows no details about the money it raised or spent. Another filing will be due Nov. 17 that should reveal spending.
The treasurer of the committee is a political consultant who previously worked for Wynn in Everett, however, and the company acknowledged its involvement after the referendum.
The revelation led the proponent of the slots parlor to cry foul, noting that those who are opposing the project often challenge its finances.
“We’re examining filing a campaign finance violation, just out of principle more than anything else,’’ said political consultant Jason Osborne. “If they’re going to call us shady and fly-by-night, this organization just popped up out of nowhere and nobody knows who’s funding it until now.’’
The project was proposed by Eugene A. McCain Jr., a developer who moved from Thailand to build a slots parlor off Revere Beach Parkway. For the Revere referendum, city election records show, McCain raised nearly $318,000 since July, almost all of it from the Delaware company of Capital Productions LLC, whose funders are unknown.
However, he’s already poured nearly twice as much into a parallel campaign he’s running statewide, through his initiative petition to change the state law to make another casino license available for him. McCain’s Horse Racing Jobs and Education Committee has spent nearly $600,000, much of it on signature-gathering efforts, a poll, and digital advertising.
The Wynn-backed committee was one of two formed to fight Tuesday’s referendum, along with “Citizens for a Better Revere,’’ which was created on Oct. 7, and also has yet to detail its spending.
In addition, the mayor’s political committee paid for Facebook ads urging voters to oppose the Revere referendum and Arrigo’s supporters campaigned door-to-door to gin up opposition.
Yet another opposition group — led by casino opponents who fought an earlier proposal in East Boston — has formed the Committee for Responsible and Sustainable Economic Development to fight the statewide ballot question. That committee has raised just $5,050.
Tuesday’s rejection by Revere was nonbinding and does not halt the ballot question. But Celeste Ribeiro Myers, a spokeswoman for that committee, said the “no’’ vote deprives McCain of what might have been an important rallying cry for the statewide vote — that Revere wanted it.
“I’m elated,’’ she said. “The city of Revere spoke loud and clear: No slots parlor. The people seem to have realized there was something fundamentally wrong with this proposal. Hopefully, it’s an indicator of how the statewide vote will go on Nov. 8.’’
Though Revere’s elected officials had previously supported proposals for a casino to be built at Suffolk Downs race track, they resisted McCain’s slot parlor plan, which emerged after the available casino licenses were already issued. Arrigo was the most outspoken opponent, leading a press conference where he and other elected officials balked at the plans presented by McCain, calling them sloppy and “Little League’’ compared to the destination resort casino they were hoping to attract.
However, Arrigo aide Joseph Gravellese, tried to distance the mayor from the official opposition efforts this week, saying the administration was not involved with a “Revere Can Do Better’’ mailer that echoed his opposition and noting that Arrigo’s campaign had only spent $222.84 to oppose the project, using Facebook ads.
Arrigo said when he made the robocall for the group, he didn’t know who was behind it. “Quite frankly, I don’t care,’’ he said. “Anything to get my message out, as long as there are no quid pro quos.’’
Wynn Resorts, one of the country’s wealthiest casino companies, recently broke ground on a $2.1 billion casino and hotel complex on the banks of the Mystic River in Everett. Wynn’s proposal beat out a rival plan for a casino at Suffolk Downs in East Boston.
As the Revere slots parlor proposal came into focus last month, DeSalvio declared Wynn’s opposition to it, but declined to say whether Wynn planned to finance an opposition campaign.
“Right now we are monitoring it,’’ he said.
DeSalvio said the slots parlor proposal would run counter to the 2011 casino law that called for a single slots parlor in Massachusetts. That slots parlor has operated in Plainville for more than a year.
If successful, DeSalvio said the proposal “would set a slippery precedent for our state,’’ allowing anyone to expand on the limited confines of the state’s casino law and build a casino.
“Voting in favor of Question 1 essentially opens the door for a slot parlor to be built in anyone’s backyard,’’ he said.
Mark Arsenault of the Gloe staff contributed to this report. Stephanie Ebbert can be reached at Stephanie.Ebbert @globe.com. Follow her on Twitter @StephanieEbbert.
