He was educated in public schools and the Dixon Academy in Covington, the seat of St. Tammany Parish, one of the suburban areas of New Orleans. He graduated from Louisiana State University in Baton Rouge in 1912. He attended Washington and Lee University in Lexington, Virginia, from 1912-1913. He then transferred to the Tulane University Law School in New Orleans, from which he received his LL.B. degree in 1914. He was admitted to the practice of law in Bogalusa, the seat of Washington Parish, where his father, whose term as governor had expired, was also then practicing law. Shortly thereafter, Sanders moved to Baton Rouge, where he would reside for most of the remainder of his life.
During World War I, Sanders served in the U.S. Army in France, having obtained the rank of captain. On October 5, 1921, he married the former Mary Briggs of Little Rock, the daughter of C.H. Briggs and the former Eugenia Tate. They had a daughter, Mary Elizabeth.
In 1934, Sanders was elected to the United States House of Representatives from the Baton Rouge-based Sixth District, a seat also held by his father from 1917-1921, and made vacant by the death of incumbent Bolivar E. Kemp. Sanders first ran in a "revolt election" in December 1933 protesting a hurriedly called special election won by Kemp's widow Lallie; the House refused to seat either Sanders or Lallie Kemp. Lallie Kemp did not run in the subsequent special election in April 1934, and Sanders was elected by defeating Agriculture Commissioner Harry D. Wilson, an ally of Long and the father of Cajun humorist Justin Wilson.
Sanders was defeated for renomination in 1936 by John K. Griffith. Sanders then staged a short comeback for the congressional seat in 1940, when he defeated Griffith. Then Sanders was toppled in the 1942 primary by the liberal James H. "Jimmy" Morrison, Sr., of Hammond, the principal city in Tangipahoa Parish. Morrison held the position until after his 1966 primary defeat at the hands of conservative Judge John Richard Rarick of St. Francisville in West Feliciana Parish.
Sanders attended meetings in 1935 to plan an anti-Long ticket in the state elections. Long accused him of involvement in a plot to assassinate him. Their conflict was bitter, but there is no evidence that either plotted to murder the others.
Sanders attended the Democratic national conventions which renominated President Franklin D. Roosevelt for third and fourth terms in 1940 and 1944. He continued his law practice in Baton Rouge. In 1960, the conservative Sanders refused to support either Democrat John F. Kennedy of Massachusetts or Republican Richard M. Nixon of California for the presidency. Instead he was an unsuccessful candidate for presidential elector on the Louisiana States Rights Party, along with future Republican Governor David C. Treen, Plaquemines Parish District Attorney Leander Henry Perez, political activist Kent Howard Courtney then of New Orleans, and former state Senator William Monroe Rainach of Claiborne Parish. He died just days before the successful Louisiana electors cast their ballots in Baton Rouge for the winning Kennedy-Lyndon B. Johnson slate.
Sanders was an active Mason and was deputy grand master of the Grand Lodge of Louisiana in 1960. He was a member of the Church of Christ, Scientist. He died in Baton Rouge and is interred in Roselawn Memorial Park there.