SACRAMENTO, Calif. — California voters were split in early returns over a statewide ballot measure touted by Gov. Gavin Newsom as a necessary step to tackle the state's ongoing homelessness crisis.

Proposition 1 would be the first major update to the state’s mental health system in 20 years. The measure needs a simple majority vote to pass. It was too early to call Tuesday night, and it could take days before the final results are tallied.

Newsom spent significant time and money campaigning on the measure's behalf, raising more than $13 million to promote it with the support of law enforcement, first responders, hospitals and mayors of major cities. Opponents raised just $1,000. He did not make any statements Tuesday as votes were counted.

“The status quo is not acceptable,” Newsom said Monday at a final campaign stop.

The Democratic governor says the proposition is needed to address the state’s homelessness crisis by boosting investments in housing and substance use programs, but social providers worry it would threaten programs that are keeping people from becoming homeless in the first place.

Republican Darlene Farnum, a retired salesperson from the Southern California suburban city of Fountain Valley, said Tuesday she voted for the proposition even though it was backed by Newsom, someone she said she disagrees with on just about everything else.

“We need to do something besides letting people die and be homeless,” she said.

Brian Frey, a programmer who lives in Sacramento, also voted for the proposition and said the issue is personal to him.

“My brother is actually homeless. He’s suffering from some mental health issues right now,” Frey said. “I think it’d be good to provide funding for treatment centers.”

The measure would restrict how counties use money from a voter-approved tax enacted in 2004 on millionaires that currently is earmarked for mental health services under broad guidelines. Revenue from the tax, now between $2 billion and $3 billion a year, provides about one-third of the state’s total mental health budget.

Counties would be required to spend about two-thirds of those funds on housing and programs for homeless people with serious mental illnesses or substance abuse problems.

Newsom wants to give the state more control over how that money is spent, but critics say it would apply one formula to all counties regardless of the size of the local homeless population and could pit programs for children against those for homeless people.

Proposition 1 also would authorize the state to borrow $6.38 billion to build 4,350 housing units, half of which would be reserved for veterans, and add 6,800 mental health and addiction treatment beds.

In an effort to ensure accurate, comprehensive tallies, counting ballots in California has become a weekslong drama that, in close contests, can transform Election Day into an election month. Mail ballots postmarked by Tuesday can arrive within seven days and are still valid. The heavy reliance on mail ballots — every voter receives one — also results in an extended tally, since each must be opened, validated and processed.

Homelessness has become one of the most frustrating issues in California and one sure to dog Newsom should he ever mount a national campaign. The state accounts for nearly a third of the homeless population in the United States; roughly 181,000 Californians are in need of housing. The state, with a current inventory of 5,500 beds, needs some 8,000 more units to treat mental health and addiction issues.

Newsom’s administration already has spent at least $22 billion on various programs to address the crisis, including $3.5 billion to convert rundown motels into homeless housing. California is also giving out $2 billion in grants to build more treatment facilities.

The proposition is touted as the final piece in Newsom's plan to reform California’s mental health system. He has already pushed for laws that make it easier to force people with behavioral health issues into treatment.