A couple hundred people have already offered to vounteeer, he says, and resumes are pouring in from across the city. An online crowd-funding campaign on the website Crowdpac has already put close to $50,000 in his coffers.
He is putting the finishing touches on what he calls an "aggressively innovative platform and plan for the city" that will "offer a set of ways to address the challenges we face and also push us to be a city that more and more people want to live and work in and where everyone can thrive."
But plenty of questions remain as Mckesson, one of the most recognizable activists to emerge from the Black Lives Matter movement, jumps into an already-deep field for the Democratic nomination. The 30-year-old Baltimore native has never held elected office, and local critics on Twitter, the platform where Mckesson has amassed more than 300,000 followers, have questioned his involvement with the city in recent years, as he has traveled around the country to different civil rights protests and begun building the police reform group Campaign Zero.
Some wonder if he can gain enough traction after filing papers for his candidacy about 10 minutes before the deadline.
That remains to be seen, of course, but what most people don't know is that, before being at the forefront in Ferguson, Missouri and meeting with the White House and interviewing with Stephen Colbert, Mckesson worked on a successful political campaign in Baltimore—that of state Sen. Bill Ferguson, a Democrat whose district is a swath of the south and southeast.
Mckesson says he learned a lot from his days knocking on doors with Ferguson in 2010, and in the state senator's campaign, he sees a path to victory he can follow.
"He too was a candidate that people bet against, that people said could never win," says Mckesson in a phone interview. "And he was able to do it. With thoughtful planning, he quickly built the infrastructure, and he had a great team of people who understood the city and had a vision for what it could be. I learned those lessons and they continue to inform the way I think about this campaign."
Reached by phone in Annapolis, Ferguson recalls how Mckesson joined his team in April and was one of his go-to people leading up to the September primary. "He was really my number one partner through the last three weeks of the campaign, as we sort of closed towards the election," he says. "And [he] was out there almost every day with me, knocking on doors across the district."
Campaigning can require long hours and down-and-dirty work, but Ferguson thinks Mckesson is suited for it.
"He's somebody that understands the power of a one-on-one conversation and how to find interest alignment so that you can move people to act," he says.
Both met while working at Baltimore City Public Schools—Ferguson as a special assistant to then-CEO Andres Alonso, and Mckesson as a human capital strategist—and collaborated on various projects related to personnel, ranging from staffing to teacher contracts, Ferguson says.
Despite their close ties, Ferguson found out about Mckesson's decison to run like everyone else, through media reports on Wednesday night and an official announcement on Medium.com. But the decision didn't surprise him.
"He's always had a passion for Baltimore and has talked about the possibilities—it's what led him to work on my campaign," he says.
Ferguson credits Mckesson with getting him to unpack his own biases and think more about race, class, and privilege in the context of politics.
Says Mckesson: "Understanding how race functions, especially in the context of cities like Baltimore, is and will continue to be important if we are to undo the impact of racism, the impact of institutional and structural disparity. And Bill gets it, Bill understands. And we have had and continue to have powerful conversations about privilege and race and equity."
That same conversation has been happening nationwide, and it is, in part, what drove Mckesson to run for mayor. In his previous advocacy, he's been "pushing systems and structures to acknowledge issues of inequity and then offering solutions."
"With this run, being mayor is about changing things from the inside," he says.
But his pitch for the job involves being removed from the political world.
"I think I'm a non-traditional candidate," he says. "I think that this is a non-traditional campaign to this city, where we have seen the failures of traditional politicians and the pathways they take."
The outsider status seems to be playing well in the presidential election, but recent polling shows three well-established politicans—former Mayor Sheila Dixon, dtate Sen. Catherine Pugh, and City Councilman Carl Stokes—in the lead.
As a fresh face, Mckesson still has a lot to prove to voters ahead of the April 26 primary, including his friend Ferguson.
"He has to prove to my constituents and constituents across the city that he's ready to lead," says Ferguson. "And I think that's what every candidate has to do. He's a friend, but at the end of the day, this is an incredibly important race, and friendships can't dictate outcomes."
No matter what happens in the weeks and months ahead, Ferguson says he expects Mckesson will elevate the campaign conversation to bigger ideas about Baltimore politics and the way they have typically operated. "I think he will challenge all of the candidates, including himself, to really confront some of the core infrastructure issues that we have in the city—and I don't mean infrastructure in the sense of roads and bridges, I mean it sort of in the people infrastructure and the systems that operate within the city to either promote access for some and not all—and question some of the core assumptions that we often ignore because of the traditional way of doing business," he says.
For now, the work is only just beginning. As for his critics, Mckesson points to his past in the school system and his years as a youth organizer. He mentions opening an after-school center at Ashburton Elementary-Middle School and training teachers.
"It's a broad range of experiences that gave me all different and important skills that I'll leverage as mayor," he says.