California’s new top-two primary system was supposed to revolutionize the state’s political process. Instead, it’s forcing candidates to revert to an antiquated practice: competing for the state party’s endorsement.

Passed by a state ballot initiative in 2010, local operatives intended the top-two primary to elect moderate and independent candidates to Congress, or at least that’s how it was sold to voters. Instead, the new primary system — which moves the top two vote recipients to the general election regardless of party affiliation — has led to a number of crowded, bitter intraparty battles, even in safe Democratic or Republican seats.

An endorsement from the state party can help distinguish a candidate in a crowded field. Most importantly for Democrats, the party’s backing can come with ground support to help low-information voters coalesce around a candidate.

“The top-two primary returns us to the days when old-fashioned, retail politics is critical, and the value of the endorsement is heightened,” said Eric Bauman, chairman of the Los Angeles Democratic Party and past delegate to the state party conventions.

Last year, the party’s endorsement helped at least two Democrats in crowded primaries: Reps. Julia Brownley and Alan Lowenthal. Brownley defeated three Democrats and a formidable independent challenger in the primary; Lowenthal emerged as the top candidate from a pool of four Democrats.

This cycle, the 31st District is a prime example of a race where a party endorsement could help a candidate emerge from a crowded field. The Democrats there are already locked in a fierce battle over local and national endorsements.

The Democratic Congressional Campaign Committee and most Democrats in the state’s congressional delegation support Redlands Mayor Pete Aguilar. But former Rep. Joe Baca is also running, along with attorney Eloise Reyes, who has support from EMILY’s List, a group that backs female candidates who support abortion rights. Local school board official Danny Tillman is in the race, too.

Democratic onlookers fear the grudge match will hurt their chances of ousting GOP Rep. Gary G. Miller, who won the election last year despite the district’s strong Democratic leaning. In 2012, Miller and another Republican won the new top-two primary after several Democratic candidates — including Aguilar — split their party’s vote.

With the same number of Democratic candidates in the race this cycle, party consultants say an endorsement could help voters coalesce around one hopeful and ensure victory.

“In a district like the 31st, voters are so inundated that they look for some cues like what’s coming in their mail, what’s coming from the teacher’s association, what’s coming from labor,” said one Democratic operative with ties to California. “And [a Democratic candidate] can’t be on any sort of slate card if there’s not an endorsement [from the state party].”

In other House races, a party endorsement could make a difference for Democrats.

In the 17th District, lawyer Ro Khanna, a Democrat, is seeking to unseat longtime Rep. Michael M. Honda. The two Democrats have already marched out long lists of supporters for this Silicon Valley-based seat.

Khanna’s challenge has forced Honda to run an aggressive primary campaign for the country’s first Asian-American majority district. In this race, a party endorsement would provide Khanna with the needed legitimacy to unseat an entrenched incumbent.

Local operatives have said it’s unlikely the party would ditch Honda for Khanna. After all, delegates stuck with Democratic Rep. Pete Stark in the middle of his tough fight against fellow Democrat and now-Rep. Eric Swalwell.

The endorsement could also play in the 10th District, where Democrat Michael Eggman has announced a challenge to vulnerable Republican Rep. Jeff Denham.

But first, Eggman must fend off astronaut Jose Hernandez, the Democrat who lost to Denham last cycle. Hernandez has told local media that he is considering a rematch.

In races where two Democrats advance past the primary, the endorsement could prove even more valuable, as the two peers must fight until the November general. Support from the state party, both in boots on the ground and monetarily, could help a candidate come out victorious in a contest.

As candidates vie for the state party’s endorsement this cycle, consultants warn that in crowded races that feat will not be easy, or even guaranteed. Delegates to California’s Democratic Party endorse a candidate through a series of conventions.

Candidates must first court the support of local party operatives, who vote in pre-endorsement conferences that take place in assembly districts around the state in mid-January.

In those conferences, a candidate must receive the support of 70 percent of the voting members to be “recommended.” Candidates who receive a recommendation are almost always certified as the endorsed candidate at the state party convention, which will be held in March 2014.

If one candidate receives more than 50 percent but less than the 70 percent threshold at the pre-endorsement caucus in January, that race will go to the state party convention.

At the convention, a candidate must receive 60 percent of the vote in order to be endorsed.

While it will be tough for a candidate in a crowded primary field to garner such a high percentage of the vote, consultants said it’s not impossible.

“They are often very contested but we are more than likely to endorse than not,” Bauman said.