UPDATE 6/8/16 7:30 a.m.: (AP) -- Hillary Clinton is now the presumptive Democratic presidential nominee with more than enough delegates to clinch the nomination but Bernie Sanders still isn't 100 percent in her rear-view mirror.
Sanders vows to soldier on through the final primary in Washington, D.C. next week. He heads to Vermont today and is in Washington tomorrow for a rally and a meeting with the president.
Clinton focused on Donald Trump yesterday, calling him "temperamentally unfit" to be president.
Trump sought to send more of a unity message in a speech yesterday, promising not to let the GOP down and saying "I understand the responsibility of carrying the mantle." Trump blasted Clinton as the defender of a "rigged" political system.
UPDATE 2:10 a.m.: Bernie Sanders is cutting into Hillary Clinton's early lead in California's Democratic presidential primary, but not by much and his path to winning the Golden State is growing steeper.
UPDATE 12:55 a.m.: Two Democrats have advanced to the November runoff in California’s U.S. Senate race.
UPDATE 10:23 p.m.: California voters have approved the lone statewide measure on Tuesday's primary ballot.
Proposition 50 asked whether the state Senate or Assembly should be allowed to suspend one of its members without pay with a two-thirds vote.
The Legislature placed the measure on the ballot two years ago after two state senators were charged with bribery and corruption and a third was convicted of perjury and voter fraud.
The Senate suspended the three but leaders said did they not have the authority to dock their pay as well.
Prop 50 was leading 77 percent to 23 percent in early returns. It takes effect immediately.
UPDATE 9:12 p.m.: The Associated Press is projecting that Democratic Attorney General Kamala Harris will advance to the general election in California's U.S. Senate race. She's leading a field of 34 candidates with nearly 40 percent of the vote in early returns.
It's too early to know whom she'll face. Another Democrat, Orange County Congresswoman Loretta Sanchez, is currently in second place with 17 percent. Former California Republican Party chair George "Duf" Sundheim is the leading GOP candidate; he's in third place with 10 percent.
Under California's primary rules, the top two finishers will advance to the November runoff.
If the two finalists are Harris and Sanchez, it would be the first statewide race since California established its "top two" primary system in the 2012 election that two candidates from the same political party faced off in the general election.
UPDATE: 8:36 p.m.: It's no surprise that Hillary Clinton has jumped out to an initial lead in California's Democratic presidential primary.
She's winning by roughly a two-to-one margin over Bernie Sanders in very early vote-by-mail ballot returns. These are ballots that were received by county elections offices well before Election Day.
The reason Clinton's early lead is no surprise is that her strongest supporters - particularly older Californians, loyal Democrats and high-propensity voters - are significantly more likely to vote by mail than Sanders's supporters, who tend to be younger and less likely to vote.
Ben Adler breaks down the California Primary Election results on NPR:
Sanders' best shot is to limit Clinton's early lead in mail ballots to single digits, then chip away throughout the evening as traditional ballots cast at polling places are counted. He may also pick up some votes as late mail ballots (those returned in-person to polling places, or postmarked by 8pm on Election Day) are counted. But counties won't even begin processing those ballots until Wednesday.
Bottom line: Don't be surprised by Clinton's early lead. Look for how big it is (a good over/under to watch for is 10%) and how rapidly Sanders makes up ground as the night wears on.
UPDATE: 8:30 p.m.: (AP) -- Donald Trump has won the Republican presidential primary in California, the biggest prize in his triumphant run to become the GOP nominee.
Trump will now go on to the national convention in July with more than enough delegates to become the official nominee. But his candidacy remains a source of controversy, with many in the GOP struggling to rally behind the brash billionaire.
Earlier Tuesday, House Speaker Paul Ryan said comments Trump made accusing a district court judge of passing a racially motivated judgment against him were the "textbook definition of a racist comment." And Sen. Mark Kirk of Illinois withdrew his support from the presumptive nominee.
UPDATE: 8:08 p.m.: Now that California polls have closed, here's what you can expect to see the rest of Tuesday night and in the days to come:
Soon after 8 p.m., the Golden State's 58 counties will post initial results. This first round of votes will be from mail ballots returned prior to the last few days.
Then, the count could slow down for a bit, as counties transport, process and count traditional (non-mail) ballots that were cast Tuesday at polling places. Those results will trickle in throughout the night (and possibly early morning hours), perhaps in multiple rounds.
But what about the mail ballots cast in the last few days, you ask? And what about the mail ballots dropped off in person Tuesday at polling places? And what about the mail ballots postmarked today (the deadline was 8pm) but still eligible to be counted as long as they arrive at county elections offices within three days?
Counties will not even begin to count those ballots until Wednesday - at the earliest - with results potentially taking days.
Finally, there are the provisional ballots - ballots whose voters' eligibility must be verified before they can be counted. That includes ballots from "no party preference" Californians who brought their nonpartisan mail ballots to polling places to exchange them for partisan ballots to vote in a presidential primary.
All of this is to say: We may not know the results of the Democratic presidential primary or U.S. Senate race for days - or even weeks.
Or, perhaps, we'll know quite quickly. Stay tuned.
UPDATE: 8:01 p.m.: Polls in California are now closed. The first results are expected shortly after 8 p.m.
1st CA results (just after 8pm): Early mail ballots— Ben Adler (@adlerben) June 8, 2016
2nd round (1-5 hours later): Poll ballots
3rd round (1-5 days later): Late mail ballots
UPDATE 5:45 p.m. California voters turned out to the polls Tuesday for the presidential primary. And while many voters are passionate about the candidates they support, others described an ambivalence about the top race.
"This election has been crazy," says Felisa Turner.
Ruth Angrisani agrees.
"But you know, we're going to vote anyway," she says.
Aja Jones says there are no "good candidates" this year.
"But you get what you get and you pick the one and hope they turn out to be the best," she says.
The election cycle has been intense, says Gary Gallery.
"It's kind of unusual, we have extremes," he says.
Kimberly Allen says picking candidates has been harder this year.
"This is the first time I've voted when I've just been very confused about what candidate is going to be right one to lead the country into the next four years," she says.
UPDATE 12:36 p.m. It was a slow start to voting in the Meadowview neighborhood of Sacramento. At the 24th Street Baptist Church, one of the polling sites, three people voted in the first hour of open polls.
Rosa Miranda-Reyes, a medical assistant at San Lucas Pediatrics, was one of them.
“You can’t complain about the government if you don’t come out and vote,” Miranda-Reyes says. “There’s no reason to be like ‘Oh, I don’t like this president, I don’t like what they’re doing with this or that.’ If you don’t make your voice heard by coming to vote, then you have no opinion.“
An hour later, as more people began going to work, the Wesleyan Riverside Church in the Pocket was relatively bustling, a steady trickle of voters pulled into the parking lot of the polling site.
“It’s your voice,” says church pastor Ruth Angrisani, as she walks in to vote. “California, it’s important, too, because it’s such a large state and has so many delegates. And so we want our voice to be heard.“
The two neighborhoods are emblematic of the challenge in achieving a representative electorate. Fewer people in lower-income, younger, more minority-heavy neighborhoods such as Meadowview typically turn out to vote than in wealthier, older and whiter neighborhoods like the Pocket.
In the 2014 general election, 45 percent of registered voters in Meadowview showed up to the polls, compared to about 60 percent in the Pocket.
- Ben Bradford / Capital Public Radio
And there’s a rare opening in the U.S. Senate. Californians haven’t had a Senate race without an incumbent on the ballot in nearly 25 years.
Under California’s “Top Two” primary system, the top two candidates – regardless of party – advance to the November runoff. And because polls show that two Democrats in the lead, it is possible we could have the first ever statewide runoff with two candidates in the same political party.
Ben Adler explains how California's primary system works:
But the polls also suggest up to half of likely GOP primary voters are undecided, so if they consolidate behind a single candidate, it is possible that a Republican could make the runoff.
There’s also one statewide measure on Tuesday's ballot. Proposition 50 would give either chamber of the Legislature the power to suspend a member without pay with a two-thirds vote.
-Ben Adler / Capital Public Radio
CapRadio provides a trusted source of news because of you. As a nonprofit organization, donations from people like you sustain the journalism that allows us to discover stories that are important to our audience. If you believe in what we do and support our mission, please donate today.