Mark Z. Barabak: Red wave vs. blue wall: Will California save or sink Democrats in November?

When it comes to national politics, California is the one state that is truly indispensable to Democrats.

Any shot at the presidency starts with its 54 electoral votes, fully one-fifth the number needed to win the White House.

Each year countless candidates come to quarry untold millions from the rich veins of campaign cash running through Hollywood, Silicon Valley and the hilltop mansions of San Francisco.

And it is California where Democrats once more turn in hopes of salvaging their hang-by-a-fingernail control of the House, or at least minimizing.