Long first ran unsuccessfully for lieutenant governor in 1932 without the support of his brother, Governor and U.S. Senator-elect Huey Long, who was pre-committed in that election to the successful candidates, Oscar K. Allen of Winnfield for governor and John B. Fournet of St. Martinville for lieutenant governor. In his autobiography, Every Man a King, Huey Long said that Earl Long's first candidacy for lieutenant governor brought forth charges of a family dynasty in the making. I sought to discourage [Earl], stating that it would be disastrous for a brother to undertake to have a brother succeed him [as governor] or to have him elected as lieutenant governor. It was already being charged that I was a dictator and that I had allowed many relatives to be placed on the state payrolls (nepotism). To have added a family name to the head of the ticket either for governor or lieutenant governor would have been disastrous to the whole ticket. My brothers and sisters, however, could not see the matter in that light. I gave everyone to understand that I was irrevocably committed to Allen for Governor and Fournet for Lieutenant Governor. ... I finally declared openly and publicly that I would not be [Earl]'s supporter for either office; that I was under lasting obligations to others; that I had done the best I could for my brother, but that I could not and would not undertake to persuade any of the candidates to whom I had given my promise to step aside. ... Not long after Huey Long's assassination, however, Earl Long handily defeated fellow Democrat Clement Murphy Mos much later a judge in Lake Charles, in the primary held for lieutenant governor in January 1936. Richard W. Leche of New Orleans was elected governor in 1936, but he resigned in scandal in 1939, and Long succeeded for eleven months to the governorship. In 1944, Long did not run for governor as many had expected but instead for his earlier position as lieutenant governor on an intra-party ticket with former U.S. Representative Lewis L. Morgan of Covington in St. Tammany Parish across Lake Ponchartrain from New Orleans. Long led the party balloting for the second position in state government, but he lost the runoff to J. Emile Verret of New Iberia, the choice of incoming Governor Jimmie Davis. His previous elected position was as a member and president of the Iberia Parish School Board. Had Lewis Morgan not entered the second primary against Jimmie Davis, Long would have become lieutenant governor without a runoff. At the time, Louisiana law provided that there would be no statewide constitutional runoff elections unless there was also a second contest for governor. That rule did not apply to state legislative races, however. In the same campaign, the Long-endorsed candidate for attorney general, state Senator Joe T. Cawthorn of Mansfield, lost to the Davis-backed Fred S. LeBlanc. Long blamed his failure to become lieutenant governor in 1944 on Louisiana Secretary of State Wade O. Martin, Jr., a former ally with whom he quarreled for many years thereafter. Years later he repaid Martin politically. In 1957, Long pushed through a new law, taking jurisdiction of insurance and voting machines from the secretary of state's office and setting up two new patronage positions. Long appointed Rufus D. Hayes of Baton Rouge as the first insurance commissioner and Drayton Boucher of Webster Parish as the commissioner of voting machines. After Boucher decided not to run for office in the 1959-1960 election cycle, Long appointed Douglas Fowler of Red River Parish, who held the job for more than twenty years. In 1948, Long was elected governor to succeed Jimmie Davis. At the time the salary was $12,000 annually. Long defeated his old rival Sam Jones by a wide margin. Eliminated in the first primary was U.S. Representative James Hobson "Jimmy" Morrison of Hammond, who made his third and final gubernatorial bid. Long appointed A.A. Fredericks as his executive secretary. Harvey Locke Carey of Shreveport was the campaign manager for northwest Louisiana and later the short-term U. S. Attorney for the United States District Court for the Western District of Louisiana. The Memphis Commercial Appeal criticized Long's election as governor in 1948. Long "promised everything but the moon"--old-age pensions, veterans bonuses, a new highway system: "[A]pparently the voters took him at his word, for they elected him by the largest majority ever given a Louisiana candidate [in a gubernatorial runoff contest]. That may be something in the nature of poetic justice, for the majority of voters will be getting exactly what was promised them, and for which they asked, whether they knew it or not." During the second half of his four-year term, Governor Long became close to Margaret Dixon, the first woman managing editor of the Baton Rouge Morning Advocate. She often advised him on political strategy. In 1951 he appointed her to the LSU Board of Supervisors. Long suffered a major heart attack in 1950, but recovered. In 1950, Long struck a deal with his intra-party rival, Mayor deLesseps Story Morrison, to return home rule to the Crescent City, which at the time was being virtually governed out of Baton Rouge. Morrison agreed not to work against Long's nephew, Russell B. Long, who was successfully seeking a full term in the United States Senate. Instead, Morrison formally endorsed one of Long's rivals, Malcolm Lafargue, the former U. S. attorney for the United States District Court for the Western District of Louisiana, based in Shreveport. Though Morrison "endorsed" Lafargue, he privately urged his followers to support Russell Long, whom he fully expected to win the race anyway.

Answer this question "Why didn't his brother support his run?" by extracting the answer from the text above.
Earl Long's first candidacy for lieutenant governor brought forth charges of a family dynasty in the making.