The outsize clout of labor in Los Angeles, for example, was underscored by the difficulty in finding a place to hold the debate that would not require candidates to cross a picket line. The Los Angeles County Federation of Labor, an umbrella group of several hundred unions representing more than 800,000 workers, has been central to national organizing campaigns like Justice for Janitors and the Fight for 15. Building power from its largely immigrant membership, the “county fed” has also been a political springboard, particularly for Latino leaders in state government.

The rise of labor in Los Angeles is relatively recent. Until quite late in the 20th century, Los Angeles was a virulently anti-union town. San Francisco was the heart of the state’s labor movement, ever since the longshoremen’s union led the 1934 general strike that shut down the city for four days.

The Bay Area was long the locus of Democratic influence and money in the decades when California was staunchly Republican. (The state’s deep blue status is also recent: Gov. Gavin Newsom, whose presidential aspirations are a popular topic in Sacramento, is only the fifth Democrat elected to lead the state in modern times.) By the 1960s, rapid growth began to shift power south, hastened by court decisions that forced the allocation of State Senate seats by population rather than by county. But Northern California, the Bay Area in particular, has remained a Democratic power base. The party’s past two governors, four United States senators and four attorneys general — not to mention House Speaker Nancy Pelosi — all have roots there.

In part, that’s because Bay Area voters consistently turn out in higher percentages, which is just another reason they feel smug. On the whole, Northerners look down on Southerners — though not of course to the degree that East Coasters do — while Southerners tend to ignore the rivalry. The different cultures, history and topography divided by the Tehachapi Mountains have confused political outsiders going back to the 1960s, when the Kennedys could never understand why they needed separate campaign operations for north and south California.

Another split, exacerbated in recent years, has been between the (reliably blue) coastal areas and the (more red though leaning purple) inland areas, particularly the huge Central Valley, which the former bodybuilder governor Arnold Schwarzenegger recently called “the abs of California.” By many measures, it is a core that needs strengthening. The valley is not home to the wealth of the coastal areas, and yet income inequality is most severe there because the poorest are so poor.