She worries Republican donors, has name recognition, and Democratic Party heavyweights are beginning to line up behind her.
US vice president Kamala Harris would be president Joe Biden's natural successor if he bowed to growing pressure and stepped aside as the Democratic candidate in the 2024 election, top Democrats say.
Now party donors, activists and officials are asking: Does she have a better chance than Biden of beating Donald Trump? Mr Biden has said repeatedly he is staying in the race.
Ms Harris, 59, a former US senator and California attorney general, would be the first woman to be president of the United States if she becomes the party's nominee and prevails in the November 5th election. She is the first African American and Asian person to serve as vice president.
Her 3-1/2 year White House tenure has been characterised by a lacklustre start, staff turnover, and early policy portfolios including migration from Central America that did not produce major successes.
As recently as last year, many inside the White House and the Biden campaign team privately worried Ms Harris was a liability for the campaign. The situation has changed significantly since then, Democratic officials have said, as she stepped forward on abortion rights and courted young voters.
She "is proud to be his running mate and looks forward to serving at his side for four more years," the Biden Harris campaign told Reuters.
Some polls favour Harris
Recent polls suggest Ms Harris could do better than Mr Biden against Mr Trump, the Republican candidate, although she would face a tight contest.
A CNN poll released on July 2nd found voters favour Mr Trump over Mr Biden by six percentage points, or 49 per cent to 43 per cent. Ms Harris also trailed Mr Trump, 47 per cent to 45 per cent, within the margin of error.
It also found independents back Ms Harris 43 per cent-40 per cent over Mr Trump, and moderate voters of both parties prefer her 51-39 per cent.
A Reuters/Ipsos poll after last week's televised debate between Mr Trump and a faltering Mr Biden found Ms Harris and Mr Trump were nearly tied, with 42 per cent supporting her and 43 per cent backing him.
Only former first lady Michelle Obama, who has never expressed any interest in joining the race, polled higher among possible alternatives to Mr Biden.
Internal polling shared by the Biden campaign after the debate shows Ms Harris with the same odds as Mr Biden of beating Mr Trump, with 45 per cent of voters saying they would vote for her versus 48 per cent for Mr Trump.
Backing of senior Democrats
Influential Democrats including US representative Jim Clyburn, who was key to Mr Biden's 2020 win; representative Gregory Meeks, a New York congressman and senior member of the Congressional Black Caucus; and Summer Lee, a House Democrat from Pennsylvania have signalled Ms Harris would be the best option to lead the ticket if Mr Biden chooses to step aside.
House minority leader Hakeem Jeffries has also privately signalled the same to lawmakers, a Congressional aide said.
Ms Harris is taken so seriously, two Republican donors told Reuters they would prefer for Mr Trump to face Mr Biden than her.
"I would prefer Biden to stay in place", rather than be replaced by Ms Harris, said Pauline Lee, a fundraiser for Mr Trump in Nevada after the June 27th debate, who said she thought Mr Biden had proved himself to be "incompetent".
And some on Wall Street, an important Democratic fundraising centre, are starting to indicate a preference.
"Biden is already behind Trump, and is unlikely to be able to overcome that gap given where his campaign is currently. Having VP Harris likely improves Democrats' odds of taking the White House," said Sonu Varghese, global macro strategist at Carson Group, a financial services company, after the debate. "There's potentially more upside for her chances than Biden's at this point."
A majority of Americans see Ms Harris in a negative light, as they do both men running for president.
Polling outlet Five Thirty Eight said 37.1 per cent of voters approve of Ms Harris and 49.6 per cent disapprove. Those numbers compare to 36.9 per cent and 57.1 per cent for Mr Biden, and 38.6 per cent and 53.6 per cent for Mr Trump.
Women, black voters, Gaza
Since the Supreme Court repealed women's constitutional right to abortion in 2022, Ms Harris has become the Biden administration's foremost voice on reproductive rights, an issue Democrats are betting on to help them win the 2024 election.
Some Democrats believe Ms Harris could energise Democratic-leaning groups whose enthusiasm for Mr Biden has faded, including Black voters, young voters and those who do not approve of Mr Biden's handling of the Israel-Hamas war.
"She would energise the Black, brown, and Asian Pacific members of our coalition ... she would immediately pull the dispirited youth of our country back into the fold," said Tim Ryan, a former Democratic congressman from Ohio, in a recent op-ed.
Democratic and Republican suburban women may also be more comfortable with her then Mr Trump or Mr Biden, he said.
As vice president, Ms Harris's public Israel strategy is identical to Mr Biden's, although she was the first senior leader of the US government to call for a ceasefire in March.
"Simply swapping out the candidate does not address the central concern" of the movement, said Abbas Alawieh, a member of the national "Uncommitted" movement that withheld votes for Mr Biden in the primary based on his support of Israel.
If Mr Biden were to step aside, there could be a competition between other Democrats to become the nominee.
If the party were then to choose another candidate over Ms Harris, some Democrats say it could lose the support of many Black voters who were critical to Mr Biden's election win in 2020.
"There is no alternative besides Kamala Harris," said Adrianne Shropshire, executive director of Black voter outreach group BlackPAC.
"If the Democratic Party thinks that they have problems now with their base being confused ... Jump over the Black woman, the vice president, and I don't think the Democratic Party actually recovers."
Left-leaning, targeted attacks
However, Ms Harris may struggle to reel in moderate Democrats and the independent voters who like Mr Biden's centrist policies, some Democratic donors said. Both parties seek independents to help pull them over the finishing line in presidential elections.
"Her greatest weakness is that her public brand has been associated with the far-left wing of the Democratic Party ... and the left wing of the Democratic party cannot win a national election," said Dmitri Mehlhorn, a fundraiser and adviser to LinkedIn co-founder and Democratic megadonor Reid Hoffman. "That is the challenge that she will have to overcome if she is the nominee."
Ms Harris would take over money raised by the Biden campaign and inherit campaign infrastructure, a critical advantage with just four months before election day on November 5th.
But any Democratic campaign still needs to raise hundreds of millions of dollars more before November to be successful, strategists say. And there, Ms Harris could be a liability.
I can tell you we have a really tough time raising money for her.
"I can tell you we have a really tough time raising money for her," said a source at the Democratic National Committee.
As a presidential candidate ahead of the 2020 election, Ms Harris lagged Mr Biden in raising money. She dropped out of the race in December 2019, the same month her campaign reported $39.3 million in total contributions. Mr Biden's campaign reported $60.9 million in the same period.
However, Mr Biden's campaign raised a record $48 million in the 24 hours after he named Ms Harris as his running mate in 2020.
Ms Harris' prosecutorial background could shine in a head-to-head debate against Mr Trump, some Democrats said.
"She is incredibly focused and forceful and smart, and if she prosecutes the case against the criminality of Donald Trump, she will rip him apart," said Mr Mehlhorn.
Republican attacks on Ms Harris are ramping up as she has been floated as a possible Biden replacement. Conservative talking heads are re-circulating criticism leveled at her during the 2020 race, including from some Democrats, that Ms Harris laughs too much, that she is untested, and unqualified.
On July 6th, the New York Post, owned by the conservative News Corp, ran a column headlined "America may soon be subjected to the country’s first DEI president: Kamala Harris," that said her political rise was because of her party's diversity, equity and inclusion "stranglehold".
Kelly Dittmar, a political science professor at Rutgers University, said the attacks are part of a long history of objectifying and denigrating women of colour in politics.
"Unfortunately, the reliance on both racist and sexist attacks and tropes against women running for office is historically common and persists to this day," said Prof Dittmar.
