Transcript for Tallahassee mayor hopes to become Florida's first black governor

In the meantime, Florida is shaping up to be a referendum on president trump, as well. New polls tonight show a very tight race. Both for governor and for senate. ABC's whit Johnson from Florida tonight. Reporter: David, this is a state that president trump won by just one percentage point back in 2016, and tonight, a bitter battle to the finish, voters with a clear voice to either celebrate or reject the trump agenda. Tonight, Tallahassee major Andrew Gillum is hoping to become Florida's first democratic governor in 24 years. A true Progressive, endorsed by former president Obama and Bernie Sanders, Gillum would also be the first black governor in state history. His opponent, Republican congressman Ron Desantis, hand-picked by president trump early on. Seen in this campaign ad using toy blocks to build trump's wall with his daughter. Build the wall! Reporter: But the race has been ugly from the start, including accusations of racism. I'm not calling Mr. Desantis a racist, I'm simply saying the racists believe he's a racist. Reporter: The Republican then taking aim at Gillum, pointing to the feds looking into corruption in Tallahassee. The fact of the matter is, he has not served honorably as the mayor. Reporter: The other big race in the senate, the incumbent Democrat bill Nelson facing a tough challenge from Republican governor Rick Scott, who's maintained president trump's support, despite their differences on several key issues. And tonight, new polls just out in Florida show both Democrats with a slight lead. But it's all about turnout, and the party that wins Florida gets an influential advantage looking ahead to 2020. David? Whit Johnson in the key state of Florida tonight. Whit, thank you.

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