Sorry,it was much more than that to him. The Johnson family got rich off the war and the buildup. They owned the second largest (right behind PA&E) construction firm in VN,and he made a bundle from them building bases,paving roads,putting in water and septic systems,etc,etc,etc.
I understand ladybird had considerable holdings in Bell Helicopter. Some even think that the switch from the Hughes LOH-6 to the Bell OH-58, in the middle of the war, had something to do with the Johnson's influence.
Remember that shoebox full of $100 bills that Sen. Herman Talmadge's wife threw out into open court during their divorce? Seems ol' "Hummin" had that box for years and years, it was the Senate's "walking-around" money. Now, where did he get that box? My guess is, he got it from Dick Russell when he died, and that Russell got it from LBJ when he became president. Robert Caro documents that LBJ invented the idea of "handy money" for campaigning with, that he got money from Brown and Root, from Sid Richardson and other Texas independent oil men, and spread it around (collecting favor-chits, of course) in the summer of 1940, saving the House of Representatives for Franklin Roosevelt, who'd been widely expected to lose the House after two full terms in office, with a Republican tide running in the country. LBJ's money turned the election around. I've no doubt that "Hummin" had that box from Landslide Lyndon himself, and that they relied for its replenishment on certain businessmen who were determined to be players. Like Earl Long said back in those same days in the 1950's, "early money buys consideration; late money buys good government".