Southern Democrats were by the 1940s a recognized bloc of legislators who were far more conservative than Northern Democrats and often sided with the GOP on critical issues, especially on matters of labor. Indeed, from about 1939 to the mid-late 1970s there was a very distinct and formidable conservative branch of the Democratic Party. The common view is that Southern Democrats turned Republican, however, with liberal Democrats making it clear that seniority was no longer the sole qualifier for holding key chairmanships through their ousters of Wilbur Mills of Arkansas, F. Edward Hebert of Louisiana, and Wright Patman and Bob Poage of Texas in 1975, Southern Democrats who wanted to hold significant power had to play ball with liberal Democrats. Although one conservative Democrat, John Jarman of Oklahoma, switched to the GOP in protest, the more common reactions were to either retire or play ball. Two conservative legislators who shifted their record significantly to the left to do so rather than joining with the Republican Party or calling it quits were Jamie Whitten of Mississippi and Walter B. Jones of North Carolina.
Case #1: Jamie Whitten

Jamie Whitten (1910-1995) stands as one of the longest-serving representatives in American history, having served in Congress from Mississippi from 1941 to 1995. Chances are my readers were alive when he was in Congress as I was. Whitten began acting as did a standard Mississippi Democrat in his day and age did: as an instinctual conservative who supported segregation. In 1962, he wrote That We May Live, a book countering Rachel Carson’s Silent Spring. Whitten hit his peaks of conservatism with dissatisfaction over Presidents Truman and Johnson, but in the 1970s his record began to moderate. Whitten would also come around to supporting civil rights legislation after 1975. In 1978, Appropriations Committee chairman George Mahon of Texas was calling it quits; he was one of the people who had survived the 1975 liberal revolt against Southern committee chairmen as he was widely regarded as capable and not obstructionist. Jamie Whitten wanted the post, but it was made clear to him that on many issues of significance he had to support the Democratic position. This he did, and during the Reagan years he was often standing in opposition to his domestic policies even though ten to twenty years earlier he would have probably stood in support. He notably described to future Senator Dick Durbin (D-Ill.) the role of Budget Committee vs. Appropriations Committee when he wanted a post on the former: “Well, if you want to be on that committee, you can be on that committee, but I want you to remember one thing, the Budget Committee deals in hallucinations and the Appropriations Committee deals in facts” (164 Cong. Rec S1881).
Although his increasingly conservative constituents were rather dismayed by his change in record, his standing in the district was sufficiently good for him to continue being reelected and he also, of course, brought home the bacon with pork barrel spending. In February 1992, Whitten suffered a major stroke and was replaced as chair of the Appropriations Committee. Although reelected that year, it was widely believed that when Whitten retired, his successor would be a Republican. Indeed, his successor was none other than Roger Wicker, who was elected in the 1994 Republican Revolution and currently serves as one of Mississippi’s senators.

Case #2: Walter B. Jones

In 1965, longtime Congressman Herbert C. Bonner died in office, and his successor was Walter Jones (1913-1992). Jones proved more conservative than his predecessor and was an opponent of President Johnson and his liberal Great Society. However, his record moderated throughout the 1970s as he grew more interested in leadership. A notable instance among what would turn out to be many in which he sacrificed principle for leadership ambitions was his vote for the bailout of New York City in 1975. As his son, Congressman Walter Jr. (R-N.C.) would recount, “He had to vote it that way. I would rather do what I think is right than to sell my political soul” (Bauerlein). He, like Whitten, proved a foe to Reagan and he voted as a party loyalist after he got the chairmanship of the Committee on Merchant Marine and Fisheries. In 1992, Jones’ district got reconfigured to be majority black and he lost renomination to Eva Clayton, dying in office shortly after. His son, Jones Jr., would win election to Congress as a Republican with the Republican Revolution of 1994, and he would take a different path than his father, emphasizing principles over power. He proved to be an independent-minded conservative with a populistic and anti-war streak. Jones maintained this with the last president he served alongside, Donald Trump. He voted against both Obamacare repeal and tax reduction legislation, which contributed to a mere 41% for his ACU score in 2017, whereas his score the previous year had been a 96%. Jones’s independence continued until his death from ALS on his 76th birthday in 2019.

References
164 Cong. Rec. S1881 (2018)
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https://www.congress.gov/crec/2018/03/21/CREC-2018-03-21-pt1-PgS1881.pdf
Bauerlein, V. (2005, May 15). Jones sails a contrarian course. The News & Observer.
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