The passage of Proposition 13 in 1978 not only set the stage for decades of political wrangling over state and local government finances, culminating in the current struggle with multibillion-dollar budget deficits, but also elevated the initiative into a powerful political tool.

Although the initiative process -- bypassing the Legislature by gathering signatures on petitions and submitting a measure to voters -- had been in the constitution for 60-plus years, it was rarely utilized until Howard Jarvis and Paul Gann shook up California with their measure to slash property taxes.

In the years since, with the Legislature largely paralyzed by ideological and partisan infighting, the initiative has evolved into a primary political weapon employed by interest groups and politicians alike to reshape public policy.

California's defining political battles have been waged through dozens of ballot measure campaigns, involving such weighty and often incendiary matters as school finance, criminal penalties, auto insurance, personal injury lawsuits, environmental protection, corporate taxation, health care access, immigrant services, bilingual education and affirmative action.

Whether the phenomenon results from justified frustration with a slow-as-molasses legislative process or the self-serving activities of professional initiative entrepreneurs, it's a fact of political life. And the stage is being set for what could be the Super Bowl of all ballot battles next November, with several dozen ballot measures, some of which are direct competitors with one another. Two dealing with strengthening or weakening Indian tribes' monopoly on slot machines typify the latter.

Not only is the potential menu of ballot measures immense -- two already qualified, 26 gathering signatures and another 26 awaiting clearance for circulation -- but the state's new governor, Arnold Schwarzenegger, may push several himself if the Legislature stalls his agenda.

Schwarzenegger has openly warned the Legislature that if it doesn't complete a massive overhaul of workers' compensation by March 1, he'll climb aboard one of the several workers' comp initiatives being circulated. "They (legislators) know how to fix it," Schwarzenegger said last week, "and this is why I gave them such a short window. ... Now, if it doesn't happen by March 1, then we go to the initiative. In November, we will have it on the ballot and then let the people vote." Schwarzenegger's tight deadline is dictated, in part, by the legal deadline to have signatures turned in by April to be certain of a count.

The threat to go to the ballot is often employed by those seeking some controversial legislation, and it often worked in the years that followed Proposition 13's passage. But later, after voters rejected a number of measures, the threat lost some of its potency. Sometimes it worked -- the California Teachers Association squeezed $1.8 billion a year in extra school money out of then-Gov. Gray Davis in 2000 after gathering enough signatures for a school finance measure that would have cost the state $6 billion more a year -- but often it didn't.

Schwarzenegger's involvement in November's many ballot measures doesn't end with workers' comp. Business groups seeking to tighten California's loose rules on unfair business practices lawsuits also want him to endorse their measure as a lever on the Legislature to act -- while lawmakers are being pressured by personal injury attorneys to resist change. The attorneys may counter with their own ballot measure. But the governor has agreed not to campaign on a couple of measures -- including a referendum to overturn a new health care mandate on employers -- as a gesture of conciliation with Democratic lawmakers.

Schwarzenegger's ability to employ the initiative as a tool for either directly legislating or pressuring the Legislature is totally dependent, however, on his presumed power to persuade voters. And that ability will be given an acid test on March 2 when voters will pass judgment on two measures -- including a $15 billion bond issue -- that Schwarzenegger wants. If he can overcome the polls and win approval, his threats to use the initiative will gain more impetus. If he fails, his position, and his initiative threat, will suffer.