(CN) - Former vice president Joe Biden stumped for Florida Democrats on Monday, just as early voting began across the state.
Biden, Senator Bill Nelson and gubernatorial candidate Andrew Gillum addressed a raucous crowd at the University of South Florida in Tampa. They implored supporters to vote and change 20 years of Republican leadership in Tallahassee.
"This election is bigger than politics," Biden told a packed gym full of about 1,000 students and retirees. "You will never vote in an election more important than this one."
In his roughly half-hour speech, Biden extolled on Nelson's career in the Senate and the historic candidacy of Gillum, who could become the state's first black governor.
"Don't tell me things cannot change," Biden said after an anecdote about former president Barack Obama's historic candidacy. "It's time! It's time!"
Nelson faces Gov. Rick Scott, who is term limited. Scott has already spent tens of millions of dollars of his own money in television and radio ads. The latest polls show the two candidates within the margin of error.
Gillum, mayor of Tallahasse, surprised many pollsters and political writers by leaping over four other well-funded candidates in the Democratic primary. He's focused his campaign on expanding Medicaid coverage and dealing with unfairness in the criminal justice system.
"Are y'all ready to flip Florida blue?" Gillum called out to his supporters at the rally.
Gillum's opponent, former congressman Ron DeSantis, has actively courted supporters of President Donald Trump, who endorsed him earlier this year. He's attacked Gillum as a socialist who will bring high crime rates to the state.
Recent polls show the two gubernatorial candidates neck-and-neck.
The rally took place a day after Gillum and DeSantis traded barbs during a CNN debate. DeSantis frequently invoked Trump and attacked Gillum's record as mayor of Tallahassee. Gillum pushed his healthcare plan and pledge to expand Medicaid.
DeSantis held his own events over the weekend, though they attracted smaller crowds than Monday's event at USF. The Navy veteran and father of two visited the state's largest retirement community, The Villages, for an event that packed a recreation center. Later in the day, he addressed a couple dozen supporters in the cramped hall of a Tampa business park office.
"I think in this race there's a huge difference," DeSantis said. "Out of the two of us, I'm the only one who has served this county. I'm the only candidate of the two that can say he's not under investigation by the FBI."
The FBI is investigating corruption in Tallahassee. Gillum maintains the FBI has told him he is the not the focus of the investigation.
"He's more radical than Moonbeam Brown," DeSantis said, referring to California's governor. "He's more radical than [New York Gov. Andrew] Cuomo. He really is."
DeSantis peppered his 20-minute speech with mentions of socialism, George Soros and the Dream Defenders, an activist group fighting police brutality that supports Gillum. He also labeled Gillum as anti-Israel.
"Is he running for governor of Florida or governor of Syria?" DeSantis said to laughs.
One of his supporters, Lisa Rachelle, described herself as an independent.
"I have different beliefs than the major political parties," said Rachelle, a flight attendant and mother of two.
A self-described "tree hugger," Rachelle said clean water is one of her major issues considering the red tide befouling the state's beaches and green algae killing fish in the interior waterways.
Rachelle said she fears Gillum will institute a state income tax.
"I like it here," she said. "I don't want [the state] to be like Portland, Oregon or New York or California."
Nate Jurewicz, 37, came to hear DeSantis speak and possibly change his mind on marijuana legalization.
"DeSantis needs to talk more about the environment and cannabis," said Jurewicz, who founded a local group, Christians for Cannabis. "That will bring in liberals, NPAs [no party affiliation] and millennials. None of those people are screaming DeSantis' name from the rooftops."
Considering the razor-thin margins on recent polls, Jurewicz said those issues could push DeSantis over the edge.
Early voting started today in the state's larger counties and continues through Nov. 4. Many candidates have targeted colleges and universities after a federal judge struck down a ban on early voting sites at those educational institutions earlier this year.
Nearly one million people have already voted in Florida's midterm elections. According to the Florida Division of Elections, approximately 930,000 voters already returned their mail-in ballots.
The general election is Nov. 6.
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