As the legislative careers of two longtime Suffolk Republicans wind down, the jockeying to replace them begins in earnest this month with a pair of primary races.

Republican voters will head to the polls June 24 to select the party’s candidate for the Suffolk County Legislature's districts 13 and 14 in November’s general election. The races are among a dozen across the county, including Republican primaries for town supervisor in Huntington and Smithtown, and Working Families primaries in Southampton.

A nine-day stretch of early voting begins Saturday. Only registered members of the parties can vote in the primary.

The legislative primaries will allow Republicans to choose a candidate to run for the seats held by Legis. Kevin McCaffrey (R-Lindenhurst), the presiding officer, and Legis. Rob Trotta (R-Fort Salonga). Both legislators are term-limited and will leave office at the end of the year.

The Suffolk Republican Committee nominated Lindenhurst Village Deputy Mayor Richard J. Renna as the candidate in District 14, which includes parts of Babylon Town, to run for McCaffrey’s seat. And the committee nominated retired NYPD Det. Salvatore Formica, 59, to run for the seat Trotta holds in District 13, which covers parts of Smithtown and Huntington.

Both candidates, who have also been nominated by the Conservative Party, face challengers for the Republican nod.

Renna, 33, faces Shawn S. Cullinane, 70, the village prosecutor for the Village of Brightwaters Justice Court.

Formica faces Frank Black, 65, of Smithtown, who has worked for the Town of Huntington for 31 years and is currently the building trades supervisor.

The winner of both races would be the presumptive favorite in the general election. Both districts have been Republican strongholds in recent elections.

Incumbent Town Supervisor Ed Smyth, a Republican, faces a primary challenge from current town board member Brooke Lupinacci.

Lupinacci, elected to the board in November 2023, faced off almost immediately against Smyth when he unveiled the Melville Town Center Overlay District plan last spring. The zoning change proposal was touted as a way to encourage developers to convert their buildings into a mixed-use property to create a walkable downtown of housing and businesses, Newsday previously reported.

Lupinacci said more research was needed before its approval last December.

Smyth touted his record of remaining under the tax cap, rebuilding the town’s infrastructure, focusing on public safety and curtailing overdevelopment.

Smyth also faces a primary challenge on the Conservative line from Dominic Spada, the former director of maritime services for the town.

The Working Families candidate for supervisor, Cooper Macco, also faces a primary challenge from Maria Delgado. Macco, a registered Democrat, is also the Democratic candidate for supervisor.

In a Working Families primary for superintendent of highways, Chris Haines faces registered Democrat Vincent Colavita.

David P. Bennardo, Gregory Grizopoulos, Eugene Cook and John Posillico are seeking the Republican nomination for two seats on the town board. Grizopoulos is a registered Conservative.

George Bergbuchler, Erick B. Greene, Jennifer A. Hebert and Stephen Anastasia are seeking the Working Families nomination for those same town board seats. Anastasia and Hebert are registered Democrats.

Incumbent Supervisor Ed Wehrheim faces off against Trotta for the Republican nod in the supervisor's race.

Wehrheim is running for his third four-year term. He said in a statement that he is running on his record, highlighting his administration’s efforts in keeping taxes low and maintaining the town’s AAA bond rating.

Trotta is running on issues that include term limits for elected town officials and pushing for "proper development" in areas such as Kings Park, where he has opposed certain projects such as apartment complex proposals.

A town board Republican primary features four candidates — Robert Semprini, Joann Tierney-Varello, Thomas J. McCarthy and Lynne C. Nowick — vying for two nominations.

Mark Bernardo and Peter M. Collins are seeking the Working Families nomination for town clerk. Bernardo is a registered Democrat.

Thomas F. Neely, Andrew Smith and Ieshia O. Galicia are seeking two Working Families nominations for town board. Neely is a registered Democrat.

Newsday's Deborah S. Morris and Jean-Paul Salamanca contributed to this report.