Elections in Louisiana—with the exception of U.S. presidential elections—follow a variation of the open primary system. Candidates of any and all parties are listed on one ballot; voters need not limit themselves to the candidates of one party. Unless one candidate takes more than 50% of the vote in the first round, a run-off election is then held between the top two candidates, who may in fact be members of the same party. In this election – the first gubernatorial election held under the state's new open primary law – the first round of voting was held on November 1, 1975.
Although no runoff was needed, because of the way the new election law was written, an unopposed runoff was held on December 13. Edwards received 430,095 votes in it, according to figures recorded by the Louisiana Secretary of State's office. The Republicans did not field a candidate for the election. The law was later rewritten to where the unopposed runoff was not required if a candidate won an outright majority in the primary. This happened in the 1983 election, when Edwards won a third non-consecutive term over Republican incumbent David C. Treen.