Democrats also have targeted the 12th District seat Republican Rep. Adam Putnam of Bartow is giving up to run for Florida agriculture commissioner. Polk County Supervisor of Elections Lori Edwards won the Democratic nomination and state Rep. Dennis Ross took the Republican race.
Kosmas, like Grayson, unseated a Republican incumbent two years ago in the Orlando area's 24th District, and the GOP has made taking back those seats a top priority.
State Rep. Sandy Adams of Orlando led Winter Park City Commissioner Karen Diebel by 560 votes, or just under 1 percentage point, with 99 percent of the expected votes counted in a five-way Republican race for the right to challenge Kosmas.
Retired Army officer Allen West defeated builder David Brady for the GOP nomination in South Florida's 22nd District. That will set up a rematch of West's race with Klein two years ago if the Democratic incumbent also wins his primary.