Supporters say they represent citizens who are sick of watching as budgets get stalled by political feuds every year. Opponents say they represent taxpayers.

But a proposition on the March 2 ballot that would make it easier for California lawmakers to pass a budget and raise taxes has emerged as a battleground for business and labor interests, with both sides making big donations to influence the vote.

Campaign finance disclosures filed Thursday show that alcohol, tobacco, oil and other interests whose products could be taxed have contributed millions to defeat Proposition 56. Among the big donors are Anheuser Busch, ChevronTexaco and Philip Morris.

The measure would allow legislators to pass a budget or tax increase with 55 percent of the vote, instead of the two-thirds majority currently required. Proposition 56 also would dock legislators' pay and expenses for every day they went beyond the annual June 15 deadline for passing a state spending plan.

If voters approve the measure, it would go into effect immediately. Democrats would have enough votes to pass the budget or raise taxes this year without a single Republican vote. Gov. Arnold Schwarzenegger, a Republican, would still have veto power.

Supporting the measure are public employee unions, which have made the bulk of the big donations to Californians for Budget Accountability, the campaign for the proposition. The California Teachers Association gave $250,000 last week; other big donors include the California State Council of Service Employees and the American Federation of State, County and Municipal Employees.

The campaign for Proposition 56 has reported collecting about $2.88 million so far, while the campaign against the measure has reported taking in more than $3.1 million.

A Field Poll released last week found that only about 20 percent of likely voters were familiar with Proposition 56.

Although both sides say they plan statewide television advertising campaigns, neither has spent any big money yet on getting out its message. Instead, supporters and opponents of Proposition 56 have been holding relatively low-cost rallies and media events in cities throughout the state.

The labor groups, which have already spent millions on the petition drive to put the measure on the ballot, have less in their coffers. Citizens for Budget Accountability reported having about $650,000 on hand as of Jan. 17. Groups opposing Proposition 56, meanwhile, reported having about $1.5 million in their campaign account.

On Thursday, the Yes on 56 campaign sent out a release drawing attention to the corporate donations that have poured into the account of the No on 56 campaign, accusing the measure's opponents of "promoting an agenda that is out of sync with the priorities of most Californians."

Al Lundeen, a spokesman for Californians Against Higher Taxes, the No on 56 campaign, said business interests have a good reason to be worried.

"A number of industries are very concerned about what this does to the California economy and whether or not it makes California a good place to do business," he said.

Polling also shows that supporters may face a tough battle. Last week's Field Poll found that 37 percent of registered voters supported the measure, while 36 percent opposed it. The rest were undecided.

"It's not starting out in a very strong position," said pollster Mark DiCamillo. "The burden of proof for any proposition is always going to be on the yes side."

Andrew Acosta, a spokesman for Californians for Budget Accountability, said the campaign believes more people will support the measure as they learn about it.

"We need to tell the voters that we're trying to solve the problem here in Sacramento that they've seen ongoing, and also give the the tools to hold the Legislature accountable," he said.