With a generous deal benefiting their workers finally in hand, union officials said late Thursday that they expect to bless White House-backed health care proposals that have stalled in recent days over organized labor’s demands.

“We will endorse it,— AFL-CIO president Richard Trumka told reporters on a Thursday evening conference call. “But [our support] is subject to the final bill and we want to see what’s done to provisions that are important to everyone out there.—

Trumka’s comments late Thursday mark a dramatic rhetorical shift by organized labor in recent weeks. Since negotiators began blending legislation from both chambers after Christmas, union bosses have been the most vocal critics of a Senate-proposed tax on “Cadillac— insurance plans that White House bean counters argue would bring down health care costs.

White House Deputy Chief of Staff Jim Messina, Democratic Congressional leaders and union officials have been bogged down this week in marathon sessions on the proposed levy. Organized labor initially lobbied vigorously to dump the tax entirely — preferring instead a House plan to tax wealthy wage-earners — but abruptly dropped their demands by mid-week and began pushing for a watered down alternative that would exclude many of their members.

According to Trumka, health care concessions reached by union leaders and the White House include a higher tax threshold for family insurance plans and the eventual exclusion of all union-negotiated plans.

The tentative deal also proposes excluding all dental and vision coverage from the benefit calculations by 2015.

“We went into it trying to figure out how to have a health care plan that was accessible, affordable and quality that would make a difference to working families in this country,— said Anna Burger, chairwoman of the labor coalition Change to Win. “The compromises that we’ve reached over the past 24 hours will really make a huge difference in terms of making sure that workers that have good health care are able to hold on to their health care.—

“We’re all very proud of what we’ve been able to do with the president and his office in getting these issues addressed,— she added.

While Trumka, Burger and other labor leaders on Thursday’s conference call defended the new health care concessions as a net positive for the general public, a labor official representing state and local employees — who received a massive carve-out in the deal — suggested that his primary job is to lobby on behalf of his union cardholders.

“A very serious part of my mission is to represent AFSCME members in the best and most meaningful way possible,— said Gerald McEntee, president of the American Federation of State, County and Municipal Employees. “But we wanted to try as part of this experience, to get something for Americans who need good health care.—

“Any number of things were good for all Americans,— he said.