When Andrew Gillum took the stage after his historic upset Tuesday night in the Democratic primary for governor, he reminded the cheering, ecstatic crowd that few had expected him to win.

He had trailed early in the crowded five-way race to replace outgoing Gov. Rick Scott. Even when his campaign began releasing polling that showed him gaining ground, he said, former Congresswoman Gwen Graham seemed likely to lead the ticket.

But his parents had taught him persistence in the face of all odds, he said. "I knew what it meant to silence and quiet the haters."

His winning primary strategy — which he had outlined for months — paid off, activating the party's substantial African-American base while bringing in younger voters and speaking to progressives frustrated with past nominees' centrist bents. Those bases — typically poorly captured by political polling — helped pull Gillum ahead of Graham 34 percent to 31 percent.

If he wins the general election against U.S. Rep. Ron DeSantis, the Tallahassee mayor could also rewrite state Democrats' political axioms for primaries to come. Gillum pulled unapologetically to the left — flouting decades of centrist campaigning — and made up the 10-to-1 spending disadvantage by using digital ads and a frugal, targeted ground game — aided by outside groups that helped get out the vote — that helped him run the table in the state's metropolitan centers including South Florida.

He also mastered the race's timing to meet voters when their interest was highest, timing his marquee endorsement from Vermont Sen. Bernie Sanders to just before early voting began and charting a bus tour through the state, from his childhood home in Richmond Heights through Gainesville to his political hometown of Tallahassee in the last few days before Election Day.

"Our problem was most people couldn't see beyond their conventional lens when it came to a race like this," said Gillum political adviser and longtime friend Sean Pittman.

Gillum's advisers and allies were well aware of his weaknesses: little name recognition and little funding. Gillum's early fundraising was hampered by news of an FBI corruption investigation into Tallahassee City Hall related to a development deal, a few months after he announced his candidacy. (Gillum has said he is not a target of the probe, though a former ally, lobbyist Adam Corey, is believed to be a central figure. Gillum and Pittman traveled twice in two years on a large group trip to Costa Rica that included Corey, though they have rejected assertions of impropriety.)

But senior campaign adviser Kevin Cate said other campaigns lacked their best asset.

"The best asset that this campaign had was Andrew Gillum, and his story and his message and his delivery," he said. "The underlying strategy is Mayor Gillum gave people something to vote for."

Campaign staff therefore put a premium on the candidate working voters in person, face-to-face, in small events in major cities across the state. Gillum went to barbershops in Sarasota. He talked to voters in Liberty City on the eve of the election. The campaign bus traversed the Interstate-4 corridor, through North Florida, into South Florida's steamy summer.

Gillum also tapped into groups like NextGen America, liberal billionaire Tom Steyer's political group, that knocked more than 81,000 doors and signed up tens of thousands of voters. That helped tap into a headline year of record turnout for both parties — the number of Democratic voters who cast their ballots was nearly 70 percent higher than it was in 2014 and 2010.

It was in the metropolitan centers Gillum ended up cementing his lead, particularly Jacksonville's Duval County. But the clincher Tuesday night was the wide margin Gillum shored up against Graham in South Florida, especially in Broward County, where vote returns were announced late. He also swept Miami-Dade, despite former Miami Beach Mayor Philip Levine's regular claim on the trail he was the "only candidate from South Florida."

"When he eventually was able to get in front of enough voters we were able to win," campaign chief strategist Scott Arceneaux said. "We had to, and did, play to our strengths."

They also sought to keep Gillum moving ahead in the last days of the race.
Though Sanders said he would grant his endorsement to Gillum about a week before it was announced, the campaign strategically timed the release to just before early voting began, Arceneaux said. "We knew we had to wait until closer to the end when we knew voters were going to pay attention."

Though Gillum's campaign was less well-funded, it persisted off regular, financial support of liberal billionaires like Steyer and George Soros, which Pittman called "several shots in the arm."

As Gillum prepares to face off against DeSantis in November, his political playbook will in part remain the same.

"We're going to continue to run a field-centric campaign that's about mobilizing voters," Arceneaux said. "We still have a lot of voters who still don't know yet who Andrew Gillum is."