Retired Sarasota Police Sgt. Jim DeNiro unseated incumbent Commissioner Joe Neunder in the Aug. 18 Republican primary for Sarasota County Commission District 4, capping a contentious campaign dominated by development, county spending and anonymous political advertising.

DeNiro received 6,627 votes, or 53.20%, to Neunder's 5,829 votes, or 46.80%, according to unofficial election results. DeNiro will face Democrat Julie London in the Nov. 3 general election.

DeNiro, a longtime Sarasota County resident who spent 30 years in law enforcement, campaigned in part on limiting development east of Interstate 75 and reducing county spending.

Neunder, a chiropractor and former Venice City Council member, was elected to the County Commission in 2022.

District 2 decided

Commissioner Mark Smith held onto his District 2 seat, defeating challenger Kristina Sargent in a universal primary that decided the race.

Smith received 8,412 votes, or 53.32%, while Sargent received 7,363 votes, or 46.68%, according to unofficial results.

Because no other candidate qualified for the seat, Smith's primary victory secured him another four-year term on the commission.

Smith, an architect and longtime Siesta Key resident, has opposed large hotel developments on the barrier island and advocated for neighborhood and flooding issues. Sargent, a political newcomer, focused her campaign on county spending, infrastructure and the county's response to flooding.

Outside spending becomes campaign issue

Anonymous political advertising became a major issue during the final weeks of the District 2 and District 4 campaigns.

Florida Trident traced campaign materials targeting Neunder and Smith to Local Government Accountability Inc., a Wyoming nonprofit. The organization's funding sources were not publicly identified.

At an Aug. 14 news conference, Neunder and Smith raised concerns about the outside campaign and questioned whether development interests were behind it. DeNiro and Sargent denied involvement with the organization.

The District 4 campaign had already centered heavily on development and infrastructure, with both Neunder and DeNiro seeking to portray the other as more closely aligned with development interests.

DeNiro also faced a Florida Elections Commission complaint questioning whether he met residency requirements for District 4. Florida Trident reported before the election that DeNiro said he had lived in the district since December 2025.

DeNiro campaigns on growth and spending

DeNiro made development and county spending central themes of his campaign, including opposition to additional development east of I-75.

Neunder, meanwhile, defended his record on the commission and raised concerns during the closing days of the campaign about anonymous groups attempting to influence the race.

After his defeat, Neunder told Sun Newspapers he did not know what factor contributed most to the result.

"I've had enough," Neunder said. "It was a good run."

DeNiro could not be reached for comment by Suncoast Searchlight or Sun Newspapers on election night.

Smith raises concerns about AI campaign material

Following his District 2 victory, Smith raised concerns about anonymous and AI-generated political material circulated during the campaign.

"This is a real warning shot, and unfortunately the result may be that the good people who want to run for office because they want to make things better, will think twice," Smith told Suncoast Searchlight.

Smith will return to the commission for a second four-year term.

DeNiro, meanwhile, advances to the Nov. 3 general election against London. The winner will represent District 4 on the Sarasota County Commission.