Sen. Dianne Feinstein has grown isolated over the years from most members of her California delegation and other Democrats in her home state, feeding a discontent among allies who tell CNN they now wish for a more engaged and energetic senior senator.

Dozens of elected California Democrats who might otherwise interact with Feinstein on a regular basis tell CNN they long ago stopped expecting to. They wish she could give advice and collaborate, tackling issues proactively as an active partner in the Senate. They're bitter about it -- and some also tell CNN that the situation means their constituents haven't been getting the work they elected their senior senator to do.

It's been six weeks since Feinstein came back to the Senate from an extended medical absence for shingles. Aides say her work level is picking back up, but her return has done little to shut down questions about her fitness for office.

CNN's outreach this month to every member of the House of Representatives from California and 20 key players in California politics reveals a level of detachment on Feinstein's part that stands out even in Washington, where congressional staffers tend to handle much of the day-to-day legislating. Asked to discuss their working relationship with the senator, many responded with extended "ums" or groans. Many spoke on the record, while others requested anonymity to speak frankly about a delicate political matter.

"The last time I spoke with her on anything face-to-face was right before the pandemic," said Rep. Raul Ruiz, estimating that conversation about designating a natural monument in his district was over three years ago.

Rep. Mike Levin said the last direct interaction with Feinstein he could pinpoint was shortly after he first won his San Diego-area seat in 2018.

"It's been quite a while," Levin said. "I don't speak with her on a regular basis, and that's been before any of the recent health challenges she's had."

"Oh boy, I can't remember. Probably when I was a freshman member," said Rep. Nanette Barragán, elected in 2016 from a district near Los Angeles.

"Gosh," said Rep. Mark Takano, a six-term Democrat, said when asked the last time they'd spoken. Pressed on any collaborations, Takano said, "Hard to say anything we've done."

"Over my 11 years in Congress, I haven't worked that closely with her," said Rep. Ami Bera.

Granted anonymity to speak frankly, one California House member said the situation is very frustrating, but also very clear.

"Californians should have two responsive, active senators," the California House member said. "And they don't."

In search of an energized, engaged partner in the Senate

Asked to pinpoint the last law in the Senate that they can remember Feinstein leading, several pointed to the Assault Weapons Ban. It passed while most current House members were still in school, and lapsed nearly 20 years ago.

The fight for more gun protections is precisely the kind of situation that has suffered from Feinstein's detachment, regardless of age or health, said Peter Ambler, a California resident and executive director of the activist group Giffords: Courage to Fight Gun Violence.

"When we launched Giffords, Senator Feinstein had been leading gun safety efforts in the Senate for decades," Ambler said. "But arriving in Washington around that time was a new generation of senators who were eager to challenge the calcified politics on the issue, take on the NRA and use the perch of the institution to shift public opinion."

"It took years to overcome Feinstein's reluctance to allow new leadership on gun safety" and let others step forward and start to shift the issue, he added.

California members of Congress say they enjoy the benefits that come with the seniority that Feinstein's staff wields effectively; their other senator is Alex Padilla, only just appointed in 2021.

A few House members from California tell CNN they don't talk to any senator, while the majority say the detachment stands out from their past experience with Feinstein and others in the job. Most say they would prefer an energized and engaged partner in their powerful senior senator.

Asked if Californians are getting two senators' worth of work, Los Angeles Rep. Jimmy Gomez said, "I think they're getting two Senate offices' worth of work, which in the end is what matters."

"A senior senator's office, and the people in it, is extremely powerful," Gomez said.

Feinstein has been showing up to more votes without arriving by wheelchair and earlier this month posed with eight fellow senators, decked out in a blue-and-white jacket, for the annual seersucker day. A Feinstein aide acknowledged that considerations around the senator's age curtailed her schedule in recent years and even more so as she was recovering from shingles, but said her work is picking back up and that she is reviewing staff memos, writing notes on news articles and reviewing every statement put out on her behalf.

Through an aide, CNN asked for an interview so that she could herself address her colleagues' complaints that she is not up to the job. Instead, the aide provided short emailed responses, adding that she had been involved in crafting them herself.

"I absolutely don't think the criticism is fair," Feinstein said in one response provided. "I do meet with California members, I answer their calls and we regularly collaborate on bills. It's not easy to have face-to-face meetings or calls with every member of the largest state delegation but that doesn't mean communication has stopped."

In another provided response, Feinstein told CNN, "like every member of Congress, I have a staff that helps me serve my constituents. I value their advice and counsel but ultimately, I make every decision." She added: "I'm back in Washington and I am working. I believe I'm still an effective voice for California."

Feinstein and her aides bristle at complaints that she's detached. Earlier this year, after Silicon Valley-area Rep. Ro Khanna called on her to resign, staff in her Senate office dug in on their history. The last time they met, they determined, was a peacemaking conversation he requested after endorsing the Democrat she beat in 2018. Khanna hasn't asked for a meeting since, an aide said.

"It's sad to see the current situation," Khanna told CNN, "and I still believe the dignified thing is for her to listen to California voters and step down with grace."

A Public Policy Institute of California poll conducted in May found that just 31% of Californians approve of the way Feinstein is handling her job, and 65% disapprove with 4% unsure. Approval has dropped 10 points since an October survey and disapproval has climbed 23 points; 41% approved in that poll, 42% disapproved and 17% were unsure.

Debating what counts as an 'active' senator

Sen. Bob Casey, a Pennsylvania Democrat, said that until just before her illness this year he had seen Feinstein be very active and asking questions in their work together on the Intelligence Committee. Even before Feinstein's medical absence, though, California members were grumbling about her absence from events back home.

"She's somewhat aloof from most members of the California delegation, aside from the few she has a close personal relationship with," said Los Angeles Rep. Brad Sherman. "On the other hand, she has done good work particularly for California and been reelected many times."

Padilla, California's other senator, told CNN that he believes the criticism of Feinstein has been "unfair."

"The work product speaks for itself," Padilla said. "Californians have two hard-working senators and two offices that are working well together, on behalf of 40 million residents of our state."

Some lawmakers think Feinstein is doing an effective job if only as a "yes" vote for Joe Biden's nominees.

Sen. Sheldon Whitehouse, a Rhode Island Democrat, stated the bottom line even more frankly on social media this week. Republicans already refused to let Feinstein be temporarily replaced on Judiciary and, if she stepped down, would have the power to refuse an organizational change for an appointment.

In other words, as Whitehouse wrote, "Mitch McConnell gets to decide whether Democrats have a Senate Judiciary majority."

Longtime allies close ranks

Walking down a hallway in the Capitol complex one day in late May, Nancy Pelosi stopped to complain to a newspaper reporter about a recent story airing concerns about Feinstein's slow convalescence.

First, she blamed "the left." Then she zeroed in on her bigger complaint.

"If she were a guy, you wouldn't even hear about it. You wouldn't even hear about it. You know it, and I know it, and I won't name important senators who were chairs of committees" who were in worse shape, Pelosi said, within earshot of several aides and other reporters.

Asked three minutes later if she felt that their fellow Californians were getting adequate representation from Feinstein, Pelosi -- whose connections with Feinstein go back to their days coming up in San Francisco - -answered firmly.

"Yes," Pelosi said that day. "Yes, I do," as she let an elevator door close off the questions.

Pelosi didn't name any senators she believed had been in worse shape than Feinstein, though there are examples -- Sens. Tim Johnson and Mark Kirk were both incapacitated for months after a brain hemorrhage and stroke, respectively. The list of senators who kept serving as they aged and struggled with health challenges includes Strom Thurmond, Robert Byrd and Thad Cochran.

The former speaker isn't the only old ally closing ranks around Feinstein.

John Garamendi, a longtime California politician and current Democratic congressman, bristled when asked about Feinstein, insisting the question was "trying to cause trouble." He said he'd spoken to the senator within the last month about flooding in his district, and, he snapped, "she was sharp, she was sane -- a lot more sane than this conversation."

Garamendi quickly ended the interview and headed up the steps of the Capitol.

Other senior members simply said they didn't want to talk about the subject.

"I don't really want to talk about Senator Feinstein," Rep. Zoe Lofgren said. Asked the last time she'd last worked with the senator, Lofgren hesitated.

"I can't think of any offhand," Lofgren, then quickly added, "but it's been often."

Rep. Jim Costa, who said he last spoke with Feinstein in February, acknowledged his old friend isn't what she was, but said he's holding out hope she might return to form.

"I want to give an opportunity to see if her recovery from the shingles and her other health issues allows her to recover to a level where she can be effective as she has been in the past," Costa said.

Then there are those concerned about the Feinstein situation prompting questions about their own futures.

"Those people who think that somehow she should get out now are people who are going to find as they age, they don't want people talking about them like that," said Rep. Maxine Waters, the 84-year-old Democrat representing parts of Los Angeles.

Race to succeed Feinstein complicates criticism about her

With three members of the state's House delegation running, campaign dynamics complicate any Feinstein discussion. That's especially true given Newsom's pledge and the candidacy of Rep. Barbara Lee, the assumed frontrunner.

Rep. Adam Schiff, the Los Angeles lawmaker whom Pelosi endorsed conditionally even before Feinstein's announcement, said he hadn't spoken with Feinstein since before she became ill. He quickly noted, "Our office works with her constantly."

Pressed if that meant he'd been working with Feinstein directly, Schiff wavered.

"We've been working with her staff," he said.

Rep. Katie Porter, a Democrat who represents Orange County, said her own last encounter with Feinstein was on a 2021 Zoom call. Porter said this is part of what she would want to address if she won Feinstein's Senate seat.

"I don't think there was a lot of House-Senate collaboration in the California delegation, period," Porter said. "That is something I would focus on rebuilding."

Lee, the Bay area congresswoman who's the longest serving of the three members running for the seat, said the last time she spoke with Feinstein was by phone in December. Calling the conversation "personal and private," she declined to discuss details.

"People have their own opinions about, 'Should she resign, should she not?'" Lee said. "Sometimes people have to also remember that there's the human side of it, and that's the side of her health and her ability to recover and to do her job."