Amid the ongoing fallout from U.S. President Joe Biden鈥檚 debate performance, talk in many top Democratic circles has already moved to who Kamala Harris鈥 running mate would be.

That鈥檚 how certain a widening group of leading party officials, operatives and donors are that the president鈥檚 slow start to salvage his campaign just won鈥檛 work, with several close allies skeptical that he is up to the reelection campaign he has pledged to stay in, based on CNN鈥檚 conversations with two dozen Democratic politicians and operatives.

Biden always says not to compare him to the almighty, but to the alternative. That鈥檚 exactly what a growing number of Democrats looking at Harris are doing.

For her part, the vice president and her staff have deliberately ignored most of the calls and texts coming their way, remaining insistently on message about both her support for Biden and her pride in sticking with him.

But Harris has already made some changes: Only after last week鈥檚 debate did her office update her schedule to put her with Biden for the Fourth of July picnic and fireworks. She has not attended the picnic before, instead keeping to her own Independence Day tradition of making a stop at a local fire station. And after Democratic governors rejected the White House鈥檚 initial offer to have her speak to them instead of Biden, she was also added to the meeting and closed it with a speech urging unity and sticking with the president.

That鈥檚 her keeping close to Biden 鈥 but it鈥檚 also Biden keeping her close.

Despite her efforts, Democratic politics has started to reshape around her 鈥 as has former President Donald Trump鈥檚 campaign, which has already begun attacking Harris. Several officials told CNN they have begun chiding donors who complain that they don鈥檛 think she can win, arguing that they need to stop and get on board with her. Other officials and advisers said plans are underway to convince Biden to immediately throw his support behind Harris, release his Democratic delegates and ask them to follow his choice. Former presidents and party leaders would then follow suit, they believe, in hopes of avoiding a contentious fight to lead the Democratic ticket.

A more open race, these top Democrats hope, would be for Harris鈥 running mate, with a focus on leading Democratic governors. North Carolina Gov. Roy Cooper and Kentucky Gov. Andy Beshear are the most discussed; the list also includes Josh Shapiro of Pennsylvania, J.B. Pritzker of Illinois and Tim Walz of Minnesota. But even that is fraught, as it would deny Harris the deference given to every other modern presidential nominee to pick their own running mate.

A Democratic senator offered an extended and very colorful metaphor for describing the movement to Harris, likening Biden and his vice president to a star quarterback who needs to be taken off the field and their backup.

鈥淲e start talking in the huddle: 鈥楧o we put in the backup QB?鈥 The backup knows our team, the backup knows the plays, the backup has played in the NFL,鈥 the senator said. 鈥淭he crowd in the stands full of passionate fans starts chanting: 鈥楶ut in the kid from Alabama!鈥 鈥楶ut in the QB from Wisconsin!鈥 All just because the backup threw an interception earlier. But we know the backup and have confidence in them.鈥

The senator said that鈥檚 the difference between the donors who are handwringing about Harris鈥 chances and many of those who are trying to focus on what the realistic options are now.

鈥淚 just want to say to all the fans: 鈥楧o you not get that they鈥檝e only played college, they鈥檝e never played a single play in the NFL? They don鈥檛 know our team or the plays?鈥欌 the senator said. 鈥淭he players are like, 鈥楾hat鈥檚 nuts. Let鈥檚 see if our star quarterback is coming back.鈥 But if he doesn鈥檛, the idea of our suddenly drafting someone from a school with a different playbook who hasn鈥檛 played a single game in the NFL is a huge risk.鈥

There are also the logistics of making a new person the Democratic nominee. Harris would be able to take over the Biden campaign fundraising and infrastructure, since she is also part of the current ticket.

鈥淚t鈥檚 a straight shot and she鈥檚 ready to roll. We鈥檝e got to be decisive, too,鈥 said Tim Ryan, the former Ohio congressman, who said he鈥檚 been getting flooded with private agreements from former colleagues and others after saying Biden needs to step aside to make room for Harris. 鈥淚t plays right into the stereotype that Democrats are weak. With one fell swoop, you can change so many different narratives.鈥

Biden campaign spokesman Kevin Munoz dismissed the speculation.

鈥淧resident Biden is our nominee, Vice President Harris is our running mate, and we will win this November,鈥 he said.

Chatter about Biden鈥檚 vs. Harris鈥 weaknesses

While several House Democrats have told colleagues they fear they will lose their seats with Harris at the top of the ticket, multiple other high level Democratic skeptics say they have already turned around on their past wariness of Harris 鈥 at least as opposed to sticking with Biden.

鈥淎re you kidding?鈥 is how the leader of one major Democratic group described the feeling when asked about preferring Harris, for all her weaknesses, to Biden in the state he鈥檚 in.

鈥淗e鈥檚 in such bad shape, but I鈥檝e also had conversations with Democrats about her from some key groups that have been skeptical in the past who believe everyone will rally to her if she鈥檚 the nominee,鈥 said a Democratic House member who has long been a Harris doubter.

An anonymously written Google document viewed by CNN titled 鈥淯nburdened by What Has Been: The Case for Kamala鈥 鈥 written by self-described 鈥渟enior operatives within Democratic political institutions鈥 鈥 has been popping up in group chats of Democratic donors and leading coalition groups. It lays out a detailed argument and plan for a campaign.

鈥淭here鈥檚 one path out of this mess, and it鈥檚 Kamala,鈥 the document reads. 鈥淜amala Harris has the strongest claim to Democratic legitimacy. She is the only candidate who can take the reins right now, instead of in late August with less than three months left to go. She has significant and widely underplayed electoral advantages. She can win.鈥

Still, even that document is full of caveats: 鈥淭his isn鈥檛 an argument about deservedness, or about why you personally should love Kamala. This is about strategy and winning in the face of unimaginable electoral stakes. The anti-Trump coalition cannot afford to discount the strengths of the nominated Democratic running mate and current vice president. She鈥檚 not the best option 鈥 she鈥檚 the only realistic option to win.鈥

Rep. Nanette Barragán, a California Democrat who supported Harris鈥 presidential campaign in 2019 and is now the chair of the Congressional Hispanic Caucus, said that though any scenario in which Biden isn鈥檛 running is 鈥渁 hypothetical situation we shouldn鈥檛 be talking about,鈥 she鈥檚 also observed the turn in the conversations she鈥檚 been hearing about the vice president.

鈥淚t鈥檚 nice to see that people are finally recognizing the value of her work and what she brings to the partnership,鈥 Barragán said.

Biden鈥檚 anemic public schedule since his debate debacle has not only raised more doubts about him, but strengthened the case for Harris, and for moving quickly.

Mini Timmaraju, the president of the abortion rights advocacy group Reproductive Freedom for All, formerly known as NARAL, said Harris already has more credibility than Biden as a leader on one of the Democrats鈥 top issues, and that no matter what happens, 鈥淵ou can鈥檛 win this election without Kamala.鈥

As for Democratic doubters, Timmaraju said, 鈥淚 don鈥檛 care if they love her or not. I know I should as an ally on the campaign. But I need them to trust the base of the party. They don鈥檛 have to like her, but they have to trust that she鈥檚 getting the job done 鈥 and saving our democracy.鈥

Pushing back on attacks on Harris

Harris loyalists have been frustrated to see the conversation about potential Biden replacements not start and stop with her. But they have been enraged by seeing donors and others talking down her chances, especially with some post-debate polls showing movement toward Trump 鈥 and a CNN poll out Wednesday showing that she would be within the margin of error against Trump, 45% to his 47%, in a hypothetical head-to-head. She was ahead of several other potential Democratic replacements.

But with panic about Biden metastasizing, it鈥檚 not just the traditional loyalists who are standing up for Harris anymore.

鈥淚f he stays in, voters need to have confidence in Harris as his running mate and potential successor,鈥 said Ezra Levin, a co-founder of the Democratic grassroots group Indivisible. 鈥淚t鈥檚 foolish and counterproductive to defend Biden by tearing down Harris.鈥

Biden has so far retained the support, publicly and mostly privately, of the Congressional Black Caucus. If he were to step aside, though, several members say they expect that support would immediately transfer to her.

That would be a point of pride for the caucus, but also one of practicality: There is no winning the election for a Democrat without huge Black turnout in places like Milwaukee, Detroit, Philadelphia and Atlanta, and they don鈥檛 believe the Democratic Party or an alternative would get there after shoving her aside 鈥 especially because none of the other leading contenders are Black.

鈥淚 actually don鈥檛 think that anybody else other than her would beat Trump because of what you鈥檇 lose in the base,鈥 said Rep. Gregory Meeks, a New York congressman and senior CBC member.

Harris鈥 preparations for Trump

Harris has considered what it would be like to run against Trump before. In late 2018, over two days of sessions with top aides to decide about running for the Democratic nomination in 2020, among the questions aides pressed her with was what she would do in a town hall-style debate with Trump, similar to the one in 2016 where the Republican infamously stalked around behind Hillary Clinton at times.

Harris鈥 answer: She鈥檇 turn around and say to him, 鈥淲hy are you being so weird?鈥

As vice president, Harris has tended to be known more for her word salads than sharp elbows like that. But for months, she had already been on an upswing in voters鈥 minds, which culminated in how she handled Biden鈥檚 debate performance in the immediate moment and afterward.

After looking over talking points suggested by Biden campaign aides to focus on some of Trump鈥檚 most radical statements and that Biden had a cold, according to several people familiar with what happened that evening, Harris came up with her line to CNN鈥檚 Anderson Cooper in the moment, arguing that a bad 90 minutes shouldn鈥檛 overshadow Biden鈥檚 three and a half years as the president.

That line, with both its defense and its honesty about what happened onstage, surprised even several close to her with its sharp delivery. It has cut through so much that in the week since, Jill Biden, multiple campaign aides and the president himself have repeated the same words almost verbatim.

Even before the last week of tail spinning, Harris had kept her focus on Trump, with a plan to take on his running mate by keeping the argument about the top of the ticket, making out anyone who would run with him as an interchangeable rubber stamp on his extremist agenda.

鈥淭he president is and will remain our party鈥檚 nominee, and Vice President Harris is proud to be his running mate and looks forward to serving at his side for four more years,鈥 Brian Fallon, Harris鈥 campaign communications director, told CNN.

Running mate options

Much of the speculative running mate conversation for Harris has centered on Cooper, the two-term governor of North Carolina, and Beshear, the younger two-term governor of Kentucky. Both, like Harris, are former state attorneys general, and both have won with Republican support. Beshear attended the Biden meeting on Wednesday in person, while Cooper attended virtually.

Cooper has a relationship with Harris that goes back years, to when they were both attorneys general. In a late 2020 interview, after Cooper won his current term and Harris was elected vice president, the governor talked about how their 鈥渞eally good relationship鈥 had continued into her Senate years, when she would occasionally consult with him on Trump judicial appointees from his home state.

鈥淪he knows what it鈥檚 like to hold a state office. I think that that鈥檚 very relatable to us as governors,鈥 Cooper said then, calling Harris 鈥渨hip smart.鈥

鈥淚 think she鈥檚 ready to do this job,鈥 Cooper said.

He demurred in that interview when asked if he could envision a Harris-Cooper ticket one day, focusing on his 40-year unbeaten record as the only Democrat to consistently win in North Carolina.

Beshear also knows how to win tough races. He鈥檚 won the top office twice in a much more Republican-heavy state and did it while talking up Democratic values like reproductive rights and looking after trans kids. He鈥檚 extremely popular in his state, and has caught national attention for being young 鈥 he鈥檚 46 鈥 and a smooth communicator who has already this year racked up invites to come speak to Democratic events in Virginia, Montana and Iowa.

Neither Cooper鈥檚 nor Beshear鈥檚 aides returned requests for comment on the speculation.

CNN鈥檚 Jeff Zeleny contributed to this report.