BATON ROUGE (AP) — Monroe Mayor Jamie Mayo joined the field of candidates Tuesday in the special election to fill the 5th District congressional seat representing northeast and central Louisiana.

Mayo, a Democrat in office for 12 years, is one of six contenders in the Oct. 19 election to fill the job being vacated by U.S. Rep. Rodney Alexander, the state’s longest-serving congressman.

Others who have filed registration paperwork for the race include: state Sen. Neil Riser, R-Columbia; state Rep. Marcus Hunter, D-Monroe; state Rep. Robert Johnson, D-Marksville; Henry Herford Jr., a Libertarian from Delhi; and Blake Weatherly, a Republican from Calhoun making his first bid for elected office.

More candidates are expected to jump in the race before qualifying at the Secretary of State’s Office ends Wednesday evening.

Mayo said he believes he can distinguish himself from others in the crowded field because he’s been a prominent political figure in the Monroe area for nearly two decades, first as a city councilman and then as mayor. He said his name recognition is strong in large portions of the sprawling district.

“Monroe is the hub of northeast Louisiana. Our media market reaches about 15 or 16 of the parishes, and I’m very involved in the entire region … I’m no stranger to over half the district,” he said.

The 5th District covers all or part of 24 parishes across northeast Louisiana, through much of central Louisiana and including all the areas that run along the Mississippi state line. It is one of the nation’s poorest congressional districts.

Mayo said he’s aware of the district’s struggles because he grew up in rural poverty.

Alexander, first elected to the U.S. House in 2002, is resigning in September to become veterans affairs secretary in Gov. Bobby Jindal’s administration.

Candidates have accused Alexander and Jindal of trying to orchestrate the sequence of events and the tight timeline for the election to help Riser win the seat, an allegation that all three men deny.

Riser is considered the front-runner in the short race. He’s received endorsements from three Republican members of Louisiana’s congressional delegation, and he’s already up with a campaign website and staff. He’s also traveled with Alexander and shown up at the congressman’s events around the district for months.

“He has a leg up in a lot of areas, and I think that’s pretty obvious,” Mayo said.

But Mayo noted he had a strong showing in a recent poll, without having even launched his campaign.

Contenders for the congressional seat varied widely in how much they expected the race to cost them, with estimates from $250,000 to more than $1 million because the sprawling district covers four TV markets.