JACKSON (AP) — Pickens Mayor Joel Gill has won the Democratic congressional primary in central Mississippi’s 3rd District.

Unofficial results Tuesday showed Gill defeated Holmes Community College sociology professor James D. Jackson of Brandon and Shawn O’Hara of Hattiesburg, who has run unsuccessfully for many Mississippi offices.

Gill, who lives outside the 3rd District, was the Democratic nominee in the district in 2008 when the seat was open. He lost to Republican Gregg Harper of Pearl.

The November ballot will have Harper, Gill and a Reform Party candidate.

Also Tuesday, Steven Palazzo has defeated Joe Tegerdine in south Mississippi’s 4th District Republican congressional primary.

Unofficial results showed Palazzo with strong showings in some of the larger counties, including his home of coastal Harrison County.

Palazzo is a military veteran, certified public accountant and first-term state lawmaker from Biloxi.

Tegerdine, a businessman from Petal, courted tea party voters in his first run for office.

Democrat Gene Taylor of Bay St. Louis has represented south Mississippi in the U.S. House since 1989.

The November ballot will have Taylor, Palazzo, a Libertarian and a Reform Party candidate.

No incumbents were on the ballot Tuesday in Mississippi; only opposing-party nominees were being chosen. Election officials reported sparse turnout in several counties, including DeSoto and Lee, which were pivotal to the most competitive race, the three-way Republican primary in the northern 1st District.

‘‘Some of the ones that usually are our big precincts, people are just not voting,’’ said Marla Treadway, a deputy circuit clerk in DeSoto County.

Early results in the 1st District showed state Sen. Alan Nunnelee of Tupelo ahead of former Eupora Mayor Henry Ross and former Fox News analyst Angela McGlowan of Oxford.

Nunnelee, Ross and McGlowan all criticized federal spending. The primary winner will face Democratic incumbent Travis Childers of Booneville and seven other candidates in November. Childers has held the seat since mid-2008.

If runoffs are needed in Mississippi, they’ll be June 22. The general election is Nov. 2.

In the Delta’s 2nd District, three were in the Republican primary: Richard Cook of Byram, a teacher who ran for the seat in 2008; George Bailey, an ordained minister, retired teacher and law enforcement officer from Clinton; and Bill Marcy of Meridian, a former Chicago police officer who ran unsuccessfully for a state House seat in Meridian in 2009.

Democrat Bennie Thompson of Bolton has represented the district since 1993 and chairs the House Homeland Security Committee.

The November ballot will have Thompson, the Republican nominee and a Reform Party candidate.

Congressional candidates aren’t required to live in the district where they’re running. Marcy, a former Chicago police officer, lives outside the 2nd District, but said that hasn’t been an issue.