There are, more or less, 40 million people living in California now, nearly twice its population when Jerry Brown began his first governorship in 1975.

But is it more, or less?

The 2020 federal census will provide the official answer, but there are rising fears among California’s political leaders, Democrats all, and myriad civil rights groups that the census will severely undercount Californians for political reasons.

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The Donald Trump administration and a Republican Congress, they say, is starving the Census Bureau of the money it would need to conduct an accurate census, especially hard-to-count poor, homeless and/or undocumented immigrant residents and children. The current plan relies on computerized responses with fewer census takers being hired to physically count those who don’t respond.

Moreover, critics complain in lawsuits that could reach the Supreme Court, the administration is deliberately discouraging census participation by immigrants with a new question about citizenship status.

The citizenship question was added by the Commerce Department, which oversees the Census Bureau, and the official rationale is that the Justice Department needs the information to better enforce the Voting Rights Act.

However, critics contend that the Justice Department request is a smokescreen to mask the administration’s hope that the question will discourage immigrants from participating, fearing that answers will expose them to deportation, even though federal law requires census data to remain confidential for 70 years after gathered.

It’s one of those instances – which seem to be increasing – in which something that appears benign, or even desirable, blows up into a political confrontation.

Hypothetically, collecting information about citizenship status would add a valuable dimension to the census, especially since the proposed question does not divide non-citizens into those with documentation and those without.

However, given the poisonous relationship between California, home to a huge population of immigrants of both varieties, and the anti-immigrant Trump White House, everything that happens feeds the conflict.

Regardless of how it is conducted, the census results will have heavy political and economic consequences for California.

We know the state’s population growth has been slowing, due to declining foreign immigration, declining birthrates, rising death rates and net losses in state-to-state population shifts.

California’s current growth rate is substantially below 1 percent a year, scarcely a third of what it was in the 1980s, when a 25 percent population growth, from 24 million to 30 million, earned the state seven new congressional seats after the 1990 census.

As growth slowed, the state gained just one new seat after the 2000 census and none after the 2010 count. Current data indicate that California’s congressional delegation could remain unchanged at 53 seats after 2020, or could drop by one seat, especially if there’s a significant undercount.

The official numbers, moreover, will be used by the state Redistricting Commission to redraw legislative and congressional districts and by local officials to redraw city council, county supervisor and school trustee districts.

The financial consequences have to do with federal funds. The state now receives about $100 billion a year from Washington, mostly to underwrite health, welfare and education programs – not counting money flowing directly to local governments.

Much of that federal aid is based on population and the California Community Foundation estimates that “every uncounted resident costs California $1,934 in annual federal funding.”

California is not being passive about the census.

Lawsuits challenging the citizenship question are one response. The new state budget allocates $90 million to encourage census participation, more than twice the $40 million that Brown initially proposed, and that’s being augmented by local governments and non-profit groups.