California Sens. Dianne Feinstein and Barbara Boxer have never been best friends. But in the weeks leading up to a tough re-election for Boxer, the two have put their sometimes competitive relationship aside to ensure the Golden State stays blue.

‘I’m her committee chairman. I’ll help her in any way I can,’ Feinstein said of Boxer. ‘I think she’s very strong, and we’ll win this race.’

The rest of California’s Democratic delegation is also pitching in. From Speaker Nancy Pelosi’s fundraising assistance to campaign appearances with others, the delegation is working together to ensure Boxer defeats GOP challenger Carly Fiorina and returns for a fourth term ‘ and those efforts are paying dividends in recent polling.

It’s not unusual for in-state colleagues to help one another, but California’s delegation isn’t known for its cohesiveness.

‘It’s such a big state, and they all have their own fiefdoms,’ one former California House staffer said.

Boxer, the firebrand, and Feinstein, the pragmatist, have avoided public confrontations, though sources said their private relationship is tense.

Boxer has gone through tight re-election campaigns in the past, but she looked increasingly vulnerable over the summer. That triggered a fear among Democrats that control of the Senate could be in play if Republicans picked up California and a handful of other seats this cycle.

Feinstein, a popular figure in California politics, has worked feverishly in recent months to help her fellow San Francisco native. Feinstein has raised money and made campaign appearances, with more expected in the weeks leading up to Election Day. Feinstein has also regularly stressed her productive working relationship with Boxer and noted the importance of having two committee chairmen represent the massive state.

‘I’ve made all kinds of public statements, done interviews,’ she said.

At least one of those statements included a strong public rebuke of Fiorina’s suggestion in June that California’s all-female Senate delegation is dysfunctional and divergent on key issues.

‘Senator Boxer and I have worked together for 18 years, as partners, in Washington and there is no daylight between us on the issues that matter most to Californians,’ Feinstein said in a statement at the time.

California House Members have given Boxer more than $42,000 in campaign donations from their leadership political action committees and an additional $26,000 in individual checks. They’ve also helped fill her coffers with considerably more cash by co-hosting fundraising events in their home districts. Last week, Pelosi and lobbyists Heather and Tony Podesta hosted a Boxer fundraiser.

Boxer has raised $18.9 million so far this cycle, compared with Fiorina’s $10.6 million. The Democratic Senatorial Campaign Committee has doled out $42,600, and President Barack Obama has visited the state twice for fundraising events. First lady Michelle Obama is going to California next month to campaign for Boxer.

The efforts may be helping: Boxer was leading Fiorina 48 percent to 40 percent in a Los Angeles Times–University of Southern California poll released Saturday.

‘Barbara Boxer is one of the best, if not the best, campaigners in the country,’ said Rep. Lynn Woolsey (D-Calif.), who chairs the Congressional Progressive Caucus. ‘Nobody’s better than she is on the platform. What she needs to count on is that the people that have supported her all along and worked with her and been partners with her don’t let her down. And we won’t.’

Woolsey represents Boxer’s former district, where the Senator is expected to sweep up votes in November. While California’s delegation is stacked with liberal members, moderates such as Reps. Dennis Cardoza and Jim Costa can help Boxer in the Central Valley, where Fiorina hopes to run up the score with independents.

The coordination has surprised some observers. California’s House Members, who don’t always work with their Senate counterparts, are also trying to save their own vulnerable incumbents, such as Rep. Jerry McNerney.

And then there are the women, who hold 18 of the 34 Democratic seats in the delegation. Many count themselves among Boxer’s admirers for her work forging an agreement on abortion in the health care bill. One staffer said Boxer won points with the group when she helped find a compromise that gave states room for flexibility from the stringent language that Rep. Bark Stupak (D-Mich.) sought. The group hasn’t forgotten, and Members from Rep. Jane Harman to Woolsey have pledged to help Boxer this fall.

‘I introduced her at an event in Brentwood and I have been with her at a couple events,’ said Harman, who predicted that Boxer would ultimately be successful. ‘She is the best campaigner on Planet Earth. I’m not sure about Mars or Venus, but she has an overdrive capacity in a campaign that is unequaled and so I rate her chances high.’