It was too late for the Establishment to get their guy elected, a sunami of voters had turned to Reagan to be the nominee.
The establishment had to let Reagan be president, take second prize with Bush as Veep and wait for 8 years to get back the control Bush presidency positioned as the Reagan third term.
HW almost blew it too. His campaign was floundering and HW was coming off as a weak leader intil one night during and interview with Dan Rather on The CBS evening news George HW parsed an insult at SPOILED Dan and Dan walking off the set during live TV. The other thing that turned HW's campaign around was the FREE WILLY HORTON ads that made hay of Dukakis's freeing the convict as governor of Taxachussetts
Also, wasn’t it not too long after Reagan was inaugurated that his attempted assassination took place? Such impatience.
Forgotten Coverage of the Reagan Assassination Attempt
Bush Son Had Dinner Plans With Hinckley Brother Before Shooting The Associated Press Domestic News
March 31, 1981, Tuesday, PM cycle
http://www.hereinreality.com/hinckley.html#.Wf4X3ltSz3g
BUSH ANGLE TO REAGAN SHOOTING STILL UNRESOLVED AS HINCKLEY WALKS A Story I Had to Leave Out of My Book
“Why did George H.W. Bush and his cabinet determine that John W. Hinckley Jr. — the man who in 1981 tried to kill the newly inaugurated President Ronald Reagan — was a lone nut, and no conspiracy, foreign or domestic, was involved? How did they arrive at this conclusion just five hours after the shooting, without any thorough examination?
And why won’t the Federal Bureau of Investigation release its documents on the shooter?”
https://whowhatwhy.org/2016/08/16/bush-angle-reagan-shooting-still-unresolved-hinckley-walks/