Democratic Rep. Loretta Sanchez addresses her supporters at Anaheim Brewery in Anaheim, Calif. Senate candidate Kamala Harris claimed one of two spots in the November runoff Tuesday, moving the state attorney general into a potentially historic election. Harris was trailed by Sanchez, a 10-term congresswoman from Orange County, who was holding steady in second place. (Ed Crisostomo/The Orange County Register via AP)

Following Tuesday’s primary, Latino Democratic lawmakers demanded that California’s Democratic Party remain neutral in the Democrat-versus-Democrat contest for the seat of retiring Sen. Barbara Boxer (D-Calif.).

Both Kamala Harris, the state’s attorney general, and Rep. Loretta Sanchez emerged from the primary (Harris turned in a performance that nearly doubled that of Sanchez) and will face each other in November. It is the first time that a Republican candidate will not be on the general election ballot for a statewide race in California.

But the contest between two Democrats promises to be no less contentious. The two women had largely avoided criticizing one another during the primary, but the tone sharpened almost immediately afterwards.

In addition to potentially straining relationships between Democrats, the contest will also test partnerships between communities of color: Harris, whose mother is from India and whose father was born in Jamaica, could become only the second black woman elected to the Senate. Sanchez, the daughter of Mexican immigrants, could be one of the first Latinas to serve in the upper chamber.

Their potential to make history has drawn attention and support from groups around the country.

Rep. Norma Torres (D), whose district is part of the Inland Empire in southern California, said she expects Sanchez to run stronger in the fall. “We know that in our June primaries Latinos traditionally don’t typically come out and vote, we know southern California specifically doesn’t come out and vote. So for the November general election, it is going to be a very, very different election.”

Torres said Harris’s strong showing in southern California was helped by support from the state Democratic Party, which backed her with a 78-to-19 delegate vote at the party convention. Torres said the party should be neutral in the general election.

“It is one thing to say there was a delegate vote and she has the Democratic Party endorsement, but it’s something very, very different if the party decides to put money into this race. That’s a very different message,” Torres said.

Her comments echoed those of Texas Rep. Filemon Vela (D), who said the state party’s behavior toward Sanchez was “disgraceful” and “insulting to Latinos all across this country.”

But the state party stands by its choice through November, noting that both candidates campaigned for the endorsement.

“I don’t want to get into strategy at this point, but I am happy to say that Democratic volunteers have come out in huge numbers to help elect Kamala Harris twice as attorney general, and she has steered our state through the economic crisis by holding Wall Street accountable,” Michael Soller, communications director for the party said via e-mail.

“We stand with our grassroots Democrats who endorsed her by nearly 80 percent and propelled her to a first-place finish in the California primary.”

Harris, 51, claimed first place in the primary in the field of 34 candidates with 40 percent of the vote, more than twice as much as Sanchez. Harris, who is from northern California, won 53 of the state’s 58 counties and she tied Sanchez in Orange County, which the congresswoman has represented for 20 years.

Sean Clegg, a consultant for Harris’s campaign couldn’t resist making a reference to The Golden State Warriors, who are leading the NBA finals and who also happen to be Harris’s hometown team: “She put up 40 points like Steph Curry,” he said referring to the celebrated point guard and shooting phenom’s second-game performance.

By contrast, he said, “Loretta Sanchez is pulling up to the starting line with four flat tires.”

But of course, Curry withered in Wednesday night, as Lebron James led the Cleveland Cavaliers to a blowout in game three.

And Sanchez’s aides and supporters suggested the same could happen to Harris as the real campaign gets underway. They predict that Latinos will come out in force for the general election and will rally around Sanchez.

Bill Carrick, Sanchez’s chief strategist, said turnout in Tuesday’s primary was low, suggesting it was because the Associated Press and NBC News Monday night declaration that Hillary Clinton was the presumptive Democratic nominee.

“I think that probably affected turnout negatively for Loretta in particular. We saw in the polling that she was doing well with millennial voters and Latino voters, both of which did not seem to have a very energized turnout,” Carrick said.

Although official turnout estimates could take weeks, he and other strategists estimate about a third of the state’s voters participated in the primary.

Sanchez will get some assists from national groups like BOLD PAC, the political organization of the Congressional Hispanic Caucus. It is chaired by her California colleague, Rep. Tony Cárdenas (D).

“Congresswoman Loretta Sanchez knows how to engage California’s Latino voters, who will turn out in strong numbers for the general election as they are historically known to do,” he said in a statement.

“She has the right message, the organizational infrastructure and the trust of Latinos across the state, which all lay the groundwork for her path to success.”

Similarly, Cesar Blanco, interim director of the Latino Victory Fund, said his group will help Sanchez with fundraising, direct mail and phone banks. “We think Loretta is in a strong position to be the first Latina senator from the state of California,” Blanco said in an interview.

Harris’s campaign vigorously pushed back on the notion that Sanchez will dominate with Latino voters. They noted Harris won in southern California, where most Latinos counties with high Latino populations.

And they pointed to Harris’s support from prominent Latinos including Delores Huerta, co-founder of the United Farm Workers; Hilda Solis, a Los Angeles County supervisor and former labor secretary; and Long Beach Mayor Robert Garcia.

“We don’t see the road for Sanchez to dramatically improve moving into November,” said pollster David Binder. “She certainly can do better, but Kamala Harris has shown to be strong with Latinos herself and we don’t see that support going away.”

Latinos make up about a quarter of California’s 17.9 million registered voters, according Paul Mitchell, owner of Redistricting Partners, a bipartisan firm that studies voter behavior. Since the beginning of the year, registration growth for Latinos has doubled, Mitchell wrote in April for Capitol Weekly, a California political blog. At least some of that growth is thought to have been influenced by Donald Trump’s rhetoric regarding his desire to build a border wall with Mexico.

Rafael Sonenshein, executive director of the Pat Brown Institute for Public Policy at Cal-State Los Angeles, said both campaigns are claiming ties to the Latino vote. But seldom can a candidate operate from “an immediate certainty that the members of their group will vote for them.”

He said it is true that Latino turnout will likely swell significantly in the primary. “and to some degree that will focus on support for Sanchez.” But he said Harris’s aides also “have a good argument that there’s not some magic formula that will suddenly turn everything around.”

Sanchez doesn’t yet have the political capital of a statewide Latino figure like former Los Angeles mayor Antonio Villaraigosa. “She’s probably going to have to work her way into the role of being the Latino candidate,” Sonenshein said.

Note: An earlier version of this article incorrectly stated that registrations among Latinos in California had grown 98 percent during the past year. That is the rate of growth since 2012.