Detractors included Democratic lawmakers who have been DeSantis' colleagues in the House.
"He can uniquely motivate the base to get that enthusiasm up", McSally said.
The three-term congressman, who makes frequent Fox News appearances, is known as an immigration hard-liner in a state where Hispanic voters hold a large sway. She will face Lea Marquez Peterson, who won the Republican nomination. After all, this is a country which has elected just two black governors in its entire 242-year history. When McCain's family said last week that he was discontinuing medical treatment, Ward speculated in a later-deleted Facebook post that the announcement was meant to hurt her campaign for Flake's seat.
In an interview with Politico, Mr Gillum said Florida would be "looking for a governor that was going to bring us together, not divide us".
"I also let him know that I would happy to help him do anything and everything we can do to rally behind his campaign to be successful in November", he said.
DeSantis credited part of his win to an endorsement from President Trump.
Trump on Twitter said that not only did DeSantis win but that "his opponent in November is his biggest dream".
The backlash against DeSantis nearly overshadowed that Trump also took shots at Gillum.
The video shows clips of DeSantis praising Trump, each followed by clips of Trump saying or doing something that mocks DeSantis's statement. Now Martha, a great U.S. Military fighter jet pilot and highly respected member of Congress, WINS BIG.
Less than a day after the 25 August 2018 announcement that Senator John McCain of Arizona had died, reports were spreading online to the effect that the state's governor had already appointed former Maricopa County Sheriff Joe Arpaio to McCain's seat in the U.S. Senate. That's despite Democrat Sinema's lead - so far - in general-election polls over Republican McSally.More news: Greg Grunberg Returning For 'Star Wars: Episode IX'
In picking Gillum, Florida Democratic voters abandoned the traditional strategy of playing to the center, and took a hard left.
DeSantis won his primary by touting his closeness to Trump. Gillum called them "beneath the intelligence of Floridians".
Marquez Peterson beat Brandon Martin, Danny Morales and Casey Welch in Tuesday's primary for Arizona's 2nd Congressional District.
The district covers the southeastern corner of Arizona from most of Tucson down to the U.S-Mexico border. Florida's registered Republicans are 83 percent white.
Arizona has an open Senate seat this cycle after Flake chose to leave office.
Marquez Peterson is the CEO of the Tucson Hispanic Chamber.
DeSantis also came out fighting, criticizing Gillum as "way, way, way too liberal for the state of Florida".
Gillum didn't make race an issue in the primary.
Gillum, the Mayor of Tallahassee, will become the first black candidate of a major party to run for governor in the Sunshine State.