New York Times bestselling author and Reagan biographer Craig Shirley tells Breitbart News Daily host Stephen K. Bannon that “Donald Trump is going to grow in power and authority thanks to the recent attacks by Mitt Romney. The party has changed and moved away from him,” meaning Romney, he added.

Shirley went on to compare Romney to Nelson Rockefeller during the Sirius XM interview, saying Nelson Rockefeller was a “spoiled sport.”

Comparing the two, said Shirley:

He (Rockefeller) didn’t help Goldwater in ’64 by walking away from the convention. He didn’t help Nixon. He was disdainful of Ronald Reagan. He was basically out for himself for many, many years. He was always on the outs of the party and he said so, especially against Conservatives. Mitt Romney has always taken the liberal establishment, country club, corporate boardroom position. And that’s because he’s a creature of that environment – that culture. … He’s no a conservative, that’s all there is to it.

Additionally, in a statement, Shirley said:

Mitt Romney will go down as a sad foot note in history, the Nelson Rockefeller of the 21st century. Too much time and money on his hands, too few ideas. … In the 60’s and 70’s, Ronald Reagan was often derided by the eastern elites, by the academia, by the establishment of the Republican Party. He was considered the George Wallace of the Republican Party, a Grade B Actor with premature orange hair, and even in 1980, when he started to break loose and head towards the nomination, the party elders in a panic went to see Gerald Ford to try to get Gerald Ford back in the race to stop Ronald Reagan.

The entire interview can be heard below. Breitbart News Daily airs from 6AM-9AM EST on Sirius XM Patriot channel 125.