(CNN) Democrat Andrew Gillum's breakthrough victory in the Florida primary this week made him the party's third African-American nominee for governor in 2018.

If that number doesn't strike you, consider this: In the history of the US, voters have elected only two African-American governors. The first, Virginia's Douglas Wilder, took office in 1990. Former Massachusetts Gov. Deval Patrick, who won consecutive terms in 2006 and 2010, is the only other. (Louisiana's Pinckney Pinchback briefly served after being elevated during Reconstruction in 1872 and David Paterson, of New York, became governor after Eliot Spitzer's resignation in March 2008.)

Wins for Gillum, Stacey Abrams in Georgia and Maryland's Ben Jealous this fall would not only be milestones in their respective states but also would register as perhaps the most stinging rebuke to date of President Donald Trump's brand of racially divisive politics.

The three Democratic nominees are each, to varying degrees, fierce advocates for a brand of progressive politics that is on the upswing among Democrats this primary season. That intersectionality is crucial to how Gillum's campaign views the electorate.

"Black voters, and particularly black women, are the bedrock of the Democratic Party, and it's incredibly important that our candidates and policies reflect that in 2018," said Gillum spokesman Geoff Burgan. "But it's also critically important for us to recognize that issues of economic fairness, race and gender all align under the progressive umbrella -- and those policies are winning at the ballot box."

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