"Duck Dynasty" star Willie Robertson resisted entreaties to run in a special congressional election this year, but he's still getting involved in the race.

Robertson is out with a new 15-second ad endorsing businessman Vance McAllister (R), the underdog in the race to replace former congressman Rodney Alexander (R-La.).

McAllister faces state Sen. Neil Riser (R) in a runoff Saturday. Riser was the top vote-getter in the open primary, taking 32 percent, compared to McAllister's 18 percent.

The 5th district is home to the Robertsons, who have the most popular cable TV reality show of all time, and they have previously appeared at events for McAllister.

Here's more on their matchup from Roll Call.