With only hours left before the first key vote on Baltimore's proposed publicly financed convention center hotel, a whirlwind weekend of dealing and strategizing appeared late yesterday to have built enough support for the project to advance.

And a major labor union is throwing its weight and possibly its money behind the idea of an affordable housing trust fund - a compromise hotel advocates hope will soften City Council opposition by linking the downtown hotel with neighborhood needs.

Councilwoman Helen L. Holton, who has opposed the idea of the city developing and owning a $305 million Hilton, said yesterday that she is willing to vote tomorrow to move the hotel bills out of committee.

But, she said, she won't ultimately support the proposal unless some of its profits help struggling neighborhoods.

"I've never not voted a bill out of committee - a bill deserves to be voted up or voted down," she said. "But that doesn't mean I'm a 'yes' to pass the bill. Those are two different things.

"I do believe we need a convention center hotel. But I'm not willing to support it without it being able to deliver something for communities."

The council is to vote tomorrow on whether to free the hotel package from the committee of the whole, where the council has debated it for more than a month. With Holton's support, the plan appears to be headed for the council floor and a second vote Aug. 15.

But that didn't stop the weekend frenzy.

To lock in support and tilt the expected close vote their way, advocates and opponents spent recent days with ears pressed to receivers, talking offers, gossip and the latest head counts of who's "yes" and who's "no."

"At the last minute things are gonna be coming out of the woodwork," said Councilman Keiffer J. Mitchell Jr.

Mayor Martin O'Malley is pushing the hotel, which would be the city's costliest public project, as the only way to save the faltering downtown convention center.

Although speculation about whether the mayor would succeed has been serious City Hall sport for a while, with the first vote looming, the intensity kicked up a notch.

"The phone has been ringing off the hook," said Councilman Kenneth N. Harris Sr., a vocal hotel opponent who said last week that he could be persuaded to support it under certain conditions. "I don't feel pressured, but I've got people pulling me on both sides."

At the center of the eleventh-hour blitz is a plan by O'Malley and City Council President Sheila Dixon, which aims to mollify community groups that have demanded the city invest in blighted neighborhoods and win last-minute support on the council.

Dixon hinted about the deal Wednesday. Yesterday her chief of staff revealed more details.

Dixon and O'Malley would create a trust fund to provide $59 million over five years to prepare sites for affordable housing. Dixon will ask the Board of Estimates on Wednesday to start the fund with $10 million from the city's budget reserve, said Beatrice L. Tripps.

Over the next four years, Baltimore would expand the pot with money from Community Development Block Grant cash and its income from the Inner Harbor Hyatt. In the second and third years, the city would tap general obligation bonds for $5 million each year.

The city would use the fund to acquire properties and clear sites. When it comes to building new affordable homes, organized labor might lend a hand.

On Friday, officials with the Washington-based AFL-CIO Housing Investment Trust expressed interest in helping, according to Tripps and Ron DeJuliis, president of the Baltimore Building and Construction Trades Council.