Wells Griffith, a Republican candidate in Alabama’s 1st District special election, went up with his first television ad on Thursday, less than a month before the Sept. 24 primary.

The 30-second “positive” spot will air on broadcast and cable stations throughout the district, and highlights Griffith’s ties to the 1st District, where his family has owned a full-service gas station for generations. The campaign spent $12,500 on the ad, according to a source with knowledge of ad buys in the district.

Griffith, a former staffer at the Republican National Committee, is running in a crowded GOP special-election primary to replace Republican Rep. Jo Bonner, who resigned in August to take a job with the University of Alabama system.

Griffith is the third candidate to go up on air.

Former state Sen. Bradley Byrne leads the pack on ad spending in the district. He is followed by Dean Young, a Republican who waged an unsuccessful primary challenge in 2012 to Bonner, who has reserved about $54,000 in cable and broadcast time up to the Sept. 24 primary, according to the source.

State Rep. Chad Fincher, is up on air with a $30,000 ad buy from GOPAC, an organization that seeks to prepare Republicans for office. And Quin Hillyer, who received the endorsement of former Sen. Rick Santorum, R-Pa., has not yet reserved television ad time for the last few weeks of the primary cycle.

Five-figure ad buys go far in this district, which is in the Mobile, Ala., media market.

Election rules in Alabama stipulate that a candidate must receive 50 percent of the vote in the primary to advance to the general. If no candidate reaches that threshold, which is unlikely in such a crowded field, a primary runoff will be held on Nov. 5.

Alabama’s 1st District is rated a Safe Republican contest by Rothenberg Political Report/Roll Call.