(CNN) Joe Biden is facing the first crisis of his yet-to-be-official, front-running 2020 Democratic presidential campaign.

An allegation by Nevada Democratic politician Lucy Flores that he once made her feel "uneasy" by smelling her hair and kissing the back of her head forced the former vice president's team into damage control mode over the weekend.

Biden said in a personal statement that while he did not recall the alleged incident, it is important for women like Flores to be heard.

It is too early to tell whether the drama represents a true emerging threat to Biden's potential campaign in the post #MeToo era or will end up as a non-disqualifying detail in the record of a colorful and sometimes controversial political figure.

Yet Biden's decision to issue a statement about the alleged incident on a day when Flores appeared on CNN's "State of the Union" clearly signaled that his team knew it had to address the situation directly before it gets worse.

A prolonged controversy over the Flores allegations could highlight Biden's own challenges in proving to Democrats that as a white, older male, he is in tune with their party's id in 2019.

A longtime Biden ally told CNN's Jeff Zeleny on Sunday there were no signs the former vice president was reassessing his 2020 plans in the wake of the allegation but cautioned Biden had still not made a final decision.

The way in which Biden's potential rivals pointedly reacted to the story hinted that it could be a liability in a nominating race in which the energy of female voters and issues important to women are already a driving force.

Those factors appeared to force Biden's hand into issuing a personal statement after he had previously relied on his team to defuse the matter.

"I believe Lucy Flores and Joe Biden needs to give an answer," Massachusetts Sen. Elizabeth Warren said on Saturday, adding that it was up to Democratic voters whether to support someone in such a position.

Minnesota Sen. Amy Klobuchar said Sunday on ABC News "This Week" that she had no reason not to believe Flores.

"I think we know from campaigns and from politics that people raise issues and they have to address them, and that's what (Biden) will have to do with the voters if he decides to get into the race."

Flores, the former Democratic nominee for lieutenant governor of Nevada, made the allegations on Friday in "The Cut," an arm of New York magazine. She wrote that Biden made her feel "uneasy, gross, and confused" in 2014 when, at a campaign rally, she said he kissed her on the back of the head.

In his statement, Biden said that he did not recall those moments in the same way. But he added: "We have arrived at an important time when women feel they can and should relate their experiences, and men should pay attention. And I will."

Biden also pledged to continue to be a strong advocate for women and equality, nodding at his work in the Senate to end violence against women.

Given the nature of the alleged incident, Flores' comments on "State of the Union" and Biden's response, it is possible the controversy could swiftly end.

Flores told CNN's Jake Tapper that she was "glad that he's willing to listen" and "glad that he is clarifying his intentions."

But she also argued that such alleged behavior was inappropriate and unprofessional, while stressing she never said it rose to the level of some kind of assault.

How the controversy could damage Biden

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Biden's 2020 campaign would have many potential strengths. He's proven at the highest level of politics. He won't be intimidated by President Donald Trump's scorched earth approach. His resilience amid personal tragedy gives him undisputed emotional depth and empathy.

Biden is also beloved among many Democrats, a factor that may partially account for his polling lead. He's respected for serving President Barack Obama for eight years while quieting his own ego and propensity for gaffes.

But the controversy and any future allegations of a similar type could be damaging nonetheless because it reflects some of his own vulnerabilities and the challenges facing a campaign that is expected to be formally launched in the coming weeks.

Running in a race that will unfold after many Democratic voters believe that Hillary Clinton — who would have been the first woman President — was beaten in an illegitimate election, was always going to be a challenge for the 76-year-old Biden — just as it is for Sen. Bernie Sanders, 77. Their gender alone explains that — at a moment when it seems to many liberals that shattering the last, highest glass ceiling in politics is more overdue than ever.

Those middle-aged-to-elderly white men who do run are under increased pressure to show they have understood the #MeToo revolution that swept politics, media and the business world. At a time of accounting for past attitudes, they are vulnerable to any examples of insufficient sensitivity to gender issues and sexual harassment from their past.

Even the language they use is under intense scrutiny — as former Texas Rep. Beto O'Rourke found when he made jokes about his wife raising their children "sometimes" with his help, for which he apologized.

Biden's supporters might deem it deeply unfair that he could be tainted by one alleged incident that he doesn't remember in a career that has endured for decades. Flores sidestepped a question on "State of the Union" about critics who may see her intervention as politically motivated.

But one problem Biden may find is that he often comes across as a hugging, back-slapping, wise-cracking, emoting male politician of the old school — a type being swept away by a new generation of radical and vibrant leaders.

Stylistically, he seems closer to Tip O'Neill, the liberal machine politician who was a Reagan-era House speaker, than Alexandria Ocasio-Cortez, the rising star of Democratic politics.

Biden's own statement on Sunday appeared to hint at the venerability of his own political brand. Indeed, his presidential campaign would have to prove either that such an approach is still relevant in the modern Democratic Party or that he is able to adapt his own political method to new circumstances.

"In my many years on the campaign trail and in public life, I have offered countless handshakes, hugs, expressions of affection, support and comfort," Biden wrote in his statement.

"And not once - never - did I believe I acted inappropriately. If it is suggested I did so, I will listen respectfully. But it was never my intention."

Biden is a tactile politician and a gregarious personality with a deeply felt, if sometimes hokey, rhetorical style.

One view of such a personality is that it's innocent and well-meaning. Another, in the changed dynamics of a new societal era, is that public hugging could come across to some women as an unacceptable assertion of male dominance by a powerful figure.

A widely scrutinized instance of Biden's demeanor occurred in 2015, at the swearing-in of Defense Secretary Ashton Carter. Biden put his hands on the shoulders of Carter's wife, Stephanie Carter, leaned over and whispered something in her ear. The moment went viral, but Stephanie Carter on Sunday came out to set the record straight.

"Last night, I received a text from a friend letting me know that picture was once again all over Twitter in connection to Lucy Flores' personal account of a 2014 encounter with Joe Biden," Carter wrote on Medium. "Let me state upfront that I don't know her, but I absolutely support her right to speak her truth and she should be, like all women, believed. But her story is not mine. The Joe Biden in my picture is a close friend helping someone get through a big day, for which I will always be grateful."

Several former Biden staffers also came to his defense on Sunday.

"Been with him in good times, bad times, quiet moments and on the biggest stages. Through it all, he was, and has always been, a huge champion for women and equality," one of the women, Elizabeth Alexander, who worked in communications for Biden in the Senate and the vice president's office, wrote on Twitter.

Biden's two political worlds

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Biden has already had to address the conflict between his two political worlds as he seeks to neutralize his handling in 1991 of the Clarence Thomas Supreme Court confirmation hearings while head of the Senate Judiciary Committee.

Biden has admitted he did not do enough to protect Anita Hill , a former co-worker of Thomas, who alleged in inflammatory televised hearings in the committee room that he had sexually harassed her.

"We knew a lot less about the extent of harassment back then, over 30 years ago," Biden said in New York last week. "She paid a terrible price. She was taken advantage of. Her reputation was attacked. I wish I could have done something."

The comments are unlikely to placate critics who believe that as committee chairman, Biden could have done far more to shield Hill.

The problem for Biden is that his repeated explanations about his record from another time only serves to underscore that he could be perceived as out of touch with some Democratic voters in the 2020 race.

The Flores controversy could also overshadow the run-up to Biden's expected presidential announcement that already is a bit of a punch line after a prolonged period on the launch pad.

Biden must also show that he has overcome a reputation as an accident-prone presidential candidate: His campaign launch in the 2008 cycle was overtaken by his own loose language, when he described Obama as "articulate" and "clean." He apologized for comments seen as racially offensive.

Biden's attempt to win the 1988 Democratic nomination foundered when he was revealed to have plagiarized remarks by Neil Kinnock, then leader of the British Labour Party.

Perhaps Biden's biggest asset in a potential 2020 race is that he is seen by some as having an excellent chance to beat Trump. That goal is so visceral for Democrats that a challenger with vulnerabilities in some areas could be embraced wholeheartedly by the party.

Sixty-two percent of Democrats polled in February by CNN and SSRS said Biden should launch a run for the party's nomination , underscoring his popularity and the value of a candidate tested in intense political warfare.

But any dent to the perception that he could beat Trump could be a significant blow to the former vice president.

The allegation against Biden by Flores pales against assertions made by prosecutors in New York — that Trump directed hush money payments against women who claimed affairs with him, claims which he has repeatedly denied.

But Trump has a visceral sense of an opponent's weaknesses and would not hesitate to use, distort and inflate the merest hint of impropriety by Biden to paper over his own vulnerabilities on a presidential debate stage.