With two Democrats on the ballot for the U.S. Senate for the first time in state history, California’s House Democrats are attempting to minimize the awkwardness that could come with the intra-party fight.

Lawmakers who serve with Orange County Rep. Loretta Sanchez are split on who to back in the race to replace Sen. Barbara Boxer: their longtime colleague or Atty. Gen. Kamala D. Harris, who won 40% of the vote to the congresswoman’s 19% in Tuesday's primary.

According to the campaigns, 17 of California’s 39 House Democrats have endorsed Sanchez and nine have endorsed Harris. The other 12 are sitting it out so far, as are Sen. Dianne Feinstein and Boxer.

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Rep. Mike Thompson (D-St. Helena) said Wednesday he’s worked with Harris on gun violence prevention, an issue that's dear to him.

“I was impressed with her. I think she’s smart, I think she would make a good U.S. senator,” Thompson said.

He said he was concerned that Sanchez told the combined editorial boards of McClatchy’s California newspapers in April that everything, including changes to the Endangered Species Act, should be on the table to address the state’s water needs. Thompson said he and Sanchez spoke about it.

“She said that was her position, and I explained to her that if it were I couldn't be with her,” Thompson said. “I like Loretta, we’re friends. But in my district the Endangered Species Act is life or death.”

Rep. Jared Huffman (D-San Rafael) has known Harris since she was a district attorney in San Fransisco. He endorsed her in January 2015 “within seconds” of finding out she was getting in the race, he said.

“I just think she is the complete package. She’s got the intellect, she got the values, she’s got the political skills, she has a compelling personal story,” Huffman said. “She’s a terrific candidate and she’s going to be a great U.S. senator.”

Huffman said he and Sanchez have talked about why he backs Harris.

“It’s always a little awkward when you have a colleague running against someone that you think very highly of, but this is a huge, high-stakes long-term proposition, who is going to be our second U.S. senator. We’ve got to get it right,” he said.

Huffman said the Democrats in California’s delegation don’t spend much time talking about the race.

“We know that within the delegation there are some fault lines that make it a little bit awkward, and so, to each his own, or her own,” he said.

Rep. Juan Vargas (D-San Diego) has been campaigning for her in Southern California.

“I strongly believe Loretta would be a fantastic senator and I’m happy to try to help her in any way. That’s in no way deprecating to Kamala,” Vargas said. “It’s an embarrassment of riches. We have two people who are just absolutely fantastic people … but I think Loretta’s the better candidate.”

As two Democrats, they should try to keep the contest from becoming bitter, he said.

“I hope there isn’t a nasty fight between the both of them, I hope they keep it on the issues, that would be good for everybody,” Vargas said.

Rep. Mark Takano (D-Riverside) campaigned for Sanchez when she won the seat over Rep. Bob Dornan in 1996.

Takano said other lawmakers ask him about Sanchez’s chances and path forward.

“Republicans and independents, I think, are up for grabs. Where do they go?” Takano said. “There is, I think, a very plausible scenario under which the race is going to be close.”

The dozen members who have stayed out of the race entirely are in a tough spot.

Rep. Jackie Speier (D-Hillsborough) said she’s still thinking about it. “It’s who you think is going to be the best representative, who is going to be the most persuasive and articulate and able to fulfill the responsibilities,” she said.

Rep. Julia Brownley (D-Westlake Village) said Harris and Sanchez each have strengths. She wants to take a close look at how her district voted in the primary before making a choice.

“We have two good candidates running and I think it’s going to really narrow in the general. I think that Loretta has a very good chance of winning, I think Kamala has a good chance, I just haven’t made a decision,” Brownley said.

Rep. Adam Schiff (D-Burbank) said he tries to stay out of contests between Democrats.

“Most of us hate when we get in between two good Democrats running for the same office, and so I haven’t gotten involved yet,” said Schiff, who may one day seek higher office in California. “I’ve done my best to remain neutral, but that’s hard when you have friends running against friends.”

California Democratic Caucus Chairwoman Zoe Lofgren said as head of the state's Democrats it’s better for her to stay on the sidelines.

“My delegation is split, so I've so far just decided to see what all my members are doing,” Lofgren said. “It’s all in good faith, it’s all friendly, but I’m just thinking, do I need to be divisive in my delegation?”

sarah.wire@latimes.com

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Read more about the 55 members of California's delegation at latimes.com/politics

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UPDATES:

11:39 a.m.: This article was updated with additional details.

This article was originally published at 8:04 a.m.