Supporters of a controversial “living wage” requirement for large District retailers made last-ditch pleas to lawmakers Monday, but hope that the D.C. Council would override a mayoral veto of the measure appeared to dwindle ahead of Tuesday’s decisive vote.

It would take nine of 13 council members to override Mayor Vincent C. Gray’s veto Thursday of the Large Retailer Accountability Act. The bill would require retailers with corporate sales of $1 billion or more operating D.C. locations of at least 75,000 square feet to pay their employees no less than $12.50 an hour in wages and benefits.

The bill has become part of a national campaign against the proliferation of low-wage jobs, and it has become interwoven locally with Wal-Mart’s plans to open several stores in the city. It passed the council on an 8 to 5 vote in July.

Activists favoring the bill have targeted several council members who oppose it, in the hope of inspiring a change of heart — particularly Tommy Wells (D-Ward 6), a mayoral candidate who is known for his progressive political leanings.

Wells said several dozen supporters of the measure attended his town hall in Anacostia on Sunday. But Wells said he remained steadfastly opposed, instead gathering support for his own bill that would institute an across-the-board minimum wage hike indexed to inflation.

He said he did not see any conflict between his progressive reputation and his opposition to the measure.

“I don’t know if that was really a progressive bill,” he said. “That was more of an old-line liberal bill,” noting that it appeared to give special advantages to union employers, such as Safeway and Giant, facing new competition from Wal-Mart.

Wells is not the only official opposed to the large-retailer bill and now proposing a broader minimum-wage increase. Gray (D) floated an unspecified minimum-wage hike in his veto letter Thursday, and council member David A. Catania (I-At Large) also announced Monday he would pursue an increase to $10.50 an hour over three years.

Council watchers have considered Catania the most likely of the five council opponents to switch his vote in an override vote, given his comments on the council dais in July suggesting he could support the bill with minor amendments. Catania did not return calls for comment Monday.

In a late attempt to persuade legislators, a coalition of groups supporting the bill on Monday released the results of a telephone poll taken Friday and Saturday showing broad support for the large-retailer measure among city residents.

The survey of 504 registered voters, done by Hart Research Associates, found 58 percent of city residents supported an override of Gray's veto, while 34 percent thought the veto should stand. The results carry a 4.5 percentage point margin of error.

The Rev. Graylan Hagler, a leader of Respect D.C., one of the groups sponsoring the poll, said the poll indicated that elected officials were not listening to their constituents.

“It's very telling,” he said. "It’s clear the mayor and council have lost the ground game. Voters don’t believe them.”

The polling did not sway the thinking of bill opponent Yvette M. Alexander (D-Ward 7), who said she was “standing strong.”

“I may even bring a Wal-Mart bag in with me tomorrow” for the final vote, she said.

Alexander said she not only expected the five opponents to stand their ground, but she said she hoped to persuade at least two of her colleagues to switch sides.

Hagler acknowledged his group had work still to be done: “This type of thing goes up all the way to the end. You never can count it until it was officially counted.”

Besides the veto-override vote, council members could vote Tuesday on two emergency measures proposed by Vincent B. Orange (D-At Large) that also deal with wage issues.

One creates a tax credit for the retailers targeted in the vetoed bill, reimbursing them $1,000 for every District employee paid at least $12.50 an hour in wages and benefits but with a yearly income of less than $50,000. The other is a sense-of-the-council endorsement of an increase in the federal minimum wage, which would have no practical effect except to possibly influence congressional debate.