In late July of 2015, Vice President Joseph R. Biden Jr. traversed the state of New York with Gov. Andrew M. Cuomo, ending the day in Queens, where they announced plans to rebuild La Guardia Airport. On a flight with Mr. Cuomo aboard Air Force Two, Mr. Biden broached a delicate subject: his own interest in the presidency.
Like most Democratic Party leaders, Mr. Cuomo was supporting Hillary Clinton, who had a wide lead in the polls. But unlike other top Democrats — including former President Barack Obama — Mr. Cuomo did not attempt to dissuade Mr. Biden from running. Instead, over what associates to both men described as a monthslong series of conversations, the governor offered a sympathetic ear to an indecisive elder statesman.
Mr. Biden later recounted in a memoir that Mr. Cuomo urged him to make a decision he could be at peace with, alluding to the similarly anguished deliberations of his father, former Gov. Mario Cuomo, decades earlier. “You’ll live with it the rest of your life,” Mr. Biden recalled the younger Mr. Cuomo saying.
Mr. Cuomo’s warm posture toward Mr. Biden raised eyebrows in Mrs. Clinton’s camp: Her aides wondered if the governor was currying favor with the Obama administration. But Mr. Cuomo offered a simpler explanation, telling allies he believed Mr. Biden would ultimately choose not to run but insisting that the vice president deserved the space to make a decision on his own terms.
The episode earned Mr. Biden’s lasting appreciation, and helped cement a personal friendship that has grown into a crucial political alliance.
Five years later, the two men have arrived together at an extraordinary moment: Mr. Biden, 77, and Mr. Cuomo, 62, have emerged as unlikely twin pillars of their party in a national crisis, Mr. Biden as its presumptive presidential nominee and Mr. Cuomo as its most forceful spokesman in a public-health emergency.
The political stakes for both men — and for their relationship — are almost unimaginably high, all the more so because of their overlapping and complementary vulnerabilities. Both are long-serving moderate stalwarts in a Democratic Party that has shifted leftward, and old-school practitioners of back-room politics in a culture that has sped up and moved online. Accentuating those challenges, Mr. Biden has struggled for years with a reputation for bombast and verbal indiscipline, while Mr. Cuomo has drawn complaints for an imperious and bullying personal style.
They have turned to each other as allies during taxing moments in the past: Much as Mr. Biden consulted with Mr. Cuomo in 2015, the governor appealed to Mr. Biden for help three years later when he faced a primary challenge from the left.
But now they are facing the greatest public trial of their lives — and counting on the resiliency of their relationship to help them navigate it.
At times, the current circumstances might have threatened to push them into competition. In recent weeks Mr. Biden has struggled to make himself heard in the din of a national crisis while Mr. Cuomo, whose daily virus updates have drawn widespread praise, has stirred Democratic fantasies of a commanding and articulate governor somehow emerging as a white-knight challenger to President Trump. Mr. Trump himself has sought to stoke some kind of feud between them, opining on Fox & Friends that Mr. Cuomo would make “a better candidate than Sleepy Joe.”
There have been moments of political friction over the last year, brief sparks between their camps if not between them. Mr. Cuomo complained privately for much of 2019 that Mr. Biden’s campaign was not responsive to governors like himself, and questioned whether the campaign was adequately prepared to contest New York’s primary. Advisers to Mr. Biden, meanwhile, were frustrated when Mr. Cuomo, who expressed early enthusiasm for Mr. Biden’s campaign, specifically noted last summer that he had not yet issued a formal endorsement.
Still, the relationship between the two men in this moment has been defined not by resentment but private consultation and public expressions of affection, people close to both men said. Mr. Biden has called Mr. Cuomo’s role in the coronavirus crisis a national “lesson in leadership,” while Mr. Cuomo went on the CNN show hosted by his younger brother, Chris, to hail Mr. Biden as a “great public servant.” Recently, Mr. Biden and Mr. Cuomo are said to have spoken about every two days, and their political advisers speak at least as frequently.
On a personal level, their allies say, Mr. Biden and Mr. Cuomo enjoy an easy rapport that has matured into a deeper friendship. In 2015, their candid conversations about the presidency took place in a period of mourning for both men: Mr. Biden had recently lost his son, Beau, to brain cancer. Mr. Cuomo was still mourning his father, who died on New Year’s Day. Mr. Biden traveled to New York for Mario Cuomo’s wake, and Mr. Cuomo attended Beau Biden’s wake in Dover, Del.
Accompanying friendship has been a political partnership. Mr. Cuomo viewed Mr. Biden as a singularly helpful ally in the Obama administration, and appealed to him personally for federal support for the rebuilding of the Tappan Zee Bridge (rechristened since as the Mario M. Cuomo Bridge.)
Mr. Biden also served as a character witness for Mr. Cuomo in his 2018 campaign when the actor and activist Cynthia Nixon accused him of corruption and dishonesty in a bitter fight for the Democratic nomination.
For Mr. Cuomo, viewed in New York as adhering to the maxim that politicians should have fewer permanent friends than permanent interests, his attitude of deference toward Mr. Biden marks a rare exception.
“He just sees Joe Biden as a morally decent guy, the same way I know he saw his own father, in that sense,” said Jay Jacobs, a close ally of Mr. Cuomo who is chairman of the New York Democratic Party.
Mr. Cuomo has never lunged at presidential races the way Mr. Biden has done repeatedly; even this time, when the Democratic field was wide open, Mr. Cuomo did little to advance the presidential ambitions that are quietly recognized among his allies.
Mr. Biden was seen as one reason for the governor’s forbearance: “I think those of us who think Andrew Cuomo would be a great president would have had a much easier time convincing him to run if Joe Biden wasn’t running,” Mr. Jacobs said.
The current election season is not the first time Mr. Biden has been upstaged during a presidential race by a governor in Albany named Cuomo.
Mr. Biden’s first such encounter was inauspicious. Seeking the Democratic nomination for president in 1987, Mr. Biden, then 44, made a dismissive remark in Iowa suggesting governors were “uniquely unequipped to understand a broad range of issues that a senator has to deal with.”
The comments drew a stern reaction from Mario Cuomo, who was then exciting liberals and overshadowing much of his party’s presidential field by publicly mulling a campaign of his own. He called Mr. Biden’s comment “one of the dumbest statements” of the election, prompting an apologetic phone call from Mr. Biden.
But Mario Cuomo never became a candidate that year, and Mr. Biden’s campaign soon disintegrated amid a plagiarism scandal.
Yet as the possibility that they would become direct competitors faded, a tone of greater respect crept into their public comments. Mario Cuomo expressed open admiration for Mr. Biden’s conduct during the confirmation hearings of Robert H. Bork, and suggested Mr. Biden could make a good choice for the keynote speaker at the 1988 Democratic convention. The slot went instead to a 41-year-old governor of Arkansas, Bill Clinton, whose rapid rise would soon put the presidency off limits to both Mr. Biden and Mr. Cuomo.
Valerie Biden Owens, the former vice president’s sister, said in an interview that it had long been evident to her that the Bidens and the Cuomos shared a common set of social values that she described as anchored in their Irish and Italian Catholic heritage. Of the elder Gov. Cuomo, Ms. Owens said, “I know my brother respected him greatly.”
“Both of them speak to, and practice, the basics of Catholic social justice, and that’s how we were raised,” Ms. Owens said.
Mr. Biden and Mr. Cuomo crossed paths in Washington in the 1990s, when Mr. Cuomo was housing secretary. But it was a few years into the new century — and through a younger generation — that the families developed a tighter bond, when Mr. Cuomo and Beau Biden were elected the attorneys general of New York and Delaware in 2006. In 2017, the former vice president wrote in his memoir that Mr. Cuomo “told me he and Beau used to commiserate about being aspiring politicians who were also the sons of well-known officeholders.” As vice president, Mr. Biden appeared beside Mr. Cuomo in several crucial moments, including during New York’s recovery from Hurricane Sandy.
Mr. Biden put his political muscle behind Mr. Cuomo in earnest in 2018, helping him against Ms. Nixon. His intervention was problematic for the left: While Ms. Nixon and her allies regularly denounced the Democratic establishment and big donors for lining up behind Mr. Cuomo, they saw little advantage in sparring with a popular figure like Mr. Biden.
Facing resistance from progressives who viewed him as an iron-fisted centrist, Mr. Cuomo’s team asked Mr. Biden to appear with him at the New York Democratic Party’s convention. Mr. Biden agreed. When they asked Mr. Biden to record a television ad for Mr. Cuomo backstage, he agreed again. When the Cuomo team asked several weeks later if Mr. Biden would record a new ad — the first one was not quite right — he agreed yet again, allowing a film crew into his Delaware home to record a commercial that soon blanketed the airwaves in New York.
Randi Weingarten, the president of the American Federation of Teachers, said Mr. Biden’s intervention in the 2018 race had helped Mr. Cuomo secure a third term. She called Mr. Biden’s speech at the state convention an important moment of validation for the governor.
“Biden is so empathetic and is seen as being such a decent man, and that was very important at that moment for Andrew Cuomo,” said Ms. Weingarten, who like other Democrats, saw a similar, perhaps anachronistic political sensibility binding the two men.
“Biden is a politician from a different age, when a sense of having somebody’s back, based upon the values you carry and the work you’ve done together, means something,” she said, adding, “That’s something that Cuomo and Biden share very, very deeply.”