Maryland legislators, bracing for an election year fight, opened their annual 90-day session Wednesday ready to take on tough partisan issues over Wal-Mart, minimum wage and election laws.

Democratic leaders and their labor allies have been pushing for overrides of two key vetoes by Gov. Robert L. Ehrlich Jr. and say they are confident of victory.

"We think that Gov. Ehrlich is looking at two losses," said Fred D. Mason Jr., president of the Maryland State and D.C. AFL-CIO.

The first and biggest test will come in the Senate on Thursday and the House of Delegates on Friday over the Fair Share Health Care Plan, which would require businesses with more than 10,000 employees in Maryland to dedicate no less than eight percent of their payroll to employee health care benefits. The second will be an effort to overturn Ehrlich's veto of a bill raising the minimum wage.

The health care bill is aimed at Wal-Mart, the giant discount retailer, which has long been a target of unions, and has been the subject of ferocious lobbying by business and labor.

The House speaker, Michael E. Busch, D-Anne Arundel, told a press conference that because it spends less on employee health care benefits, Wal-Mart has an "unfair advantage" over other businesses.

"This is good for small businesses, as well as the right thing to do," he said.

The Wal-Mart bill has drawn national attention because it could set a precedent for other states to follow if it is passed and survives the inevitable legal challenge.

"It will make Maryland the laughingstock of the country and drive businesses out," said Del. Michael D. Smigiel, Sr., an Eastern Shore Republican.

Ehrlich and other opponents of the bill predict that a law requiring large businesses to spend for health benefits will eventually be expanded, as the Legislature might be unable to resist efforts to lower the current threshold of 10,000 employees.

"Getting something done in the legislature is often an incremental task," said Will Burns, a spokesman for the Maryland Chamber of Commerce. He said he believes the Wal-Mart bill is not the end of the debate and its supporters are only trying to get their "foot in the door."

Democrats are also looking at the Wal-Mart vote to score a stinging political victory over the Republican incumbent, Ehrlich, who will be running for re-election this fall. At a luncheon meeting cum pep rally on Tuesday, an exuberant Senate President, Thomas V. Mike Miller, Democrat of Southern Maryland, said of the GOP leadership: "They're going to be flying high and we're going to shoot them down. We're going to put them in the ground and it'll be 10 years before they come out again." Predictably, Republicans did not find the rhetoric to their liking.

"If that kind of language keeps coming out like it did yesterday, it's going to be a difficult year," said the Senate minority leader, J. Lowell Stoltzfus, an Eastern Shore Republican.

But the mood in the State House Wednesday belied the tough partisan battles looming as both houses of the assembly took on a warm, almost festive atmosphere typical of the opening day.

Legislators, lobbyists and journalists mingled in the hall before the noon commencement while fresh-faced pages in gray jackets emblazoned with the Maryland state flag scurried from desk to desk, stuffing each with bill books.

It was a family affair also, with many senators and delegates introducing their spouses and children to colleagues. The occasional baby's cry cut through the speeches on the floor of the two chambers.

Both Busch and Miller were re-elected to their leadership posts in one of the few bits of important business necessary on opening day.

More typical was the appearance of major political figures from around the state. This being an election year, most of the major candidates for governor and U.S. Senate mingled in the hallways and lobbies, glad-handing friends and supporters.

Though the first days of the session will be dominated by the fight to override Ehrlich's vetoes of both the Wal-Mart bill and the bill raising the minimum wage a dollar an hour, there will be ample opportunity for controversy in the weeks to come.

Legislation dealing with stem cell research, the penalties for sex offenders, teacher pensions, education funding and a budget surplus of a tempting $1.5 billion are expected to be on the agenda.

Capital News Service contributed to this report.