The dynamics of American Protestantism have changed drastically since the 1920s, Sinclair Lewis' heyday. The modernist-fundamentalist split had not yet been fully completed at the time. At present, liberal Protestantism and its conservative opposition are wholly divorced. Sociologists treat mainline Protestants and evangelicals to be as distinct from each other as both are from Catholics. Evangelicals are friendlier at least towards conservative Catholics than at any time since the Reformation. The rise of dispensational theology in evangelical circles and the impact of the Holocaust have routed past tendencies toward anti-Semitism, although many Jews still distrust evangelicals. White segregationist sentiments have likewise disappeared. By the 1980s, conservative Baptist preachers like Jerry Falwell and W.A. Criswell apologized for the pro-segregation statements they had made in the 1950s.
While Mike Huckabee is a nanny state advocate and may be playing the Christian card unfairly against Mitt Romney, it is equally unfair for Ron Paul to imply that Huckabee is a fascist by quoting a long-dead author out of historical context.
Ron Paul did not call Huckabee a Fascist, but he did point out that everything is not always what it seems. That was his point. Frankly, I do not think Huckabee supports a Mussolini style Corporate/Totalitarian State. But his "Christianity" seems a bit confused, when it is used to justify his past support for Hispanic migrants taking the jobs of native Arkansans. Neither the concept of a Universal God, nor the evangelical pursuit of winning adherence to that Universal God, can rationally support the principle of failing in a duty to provide for your own posterity. It is in that failure that Governor Huckabee's wearing of Faith upon sleeve becomes really suspect.
But all Dr. Paul was really saying by the Sinclair Lewis quote, is don't trust appearances--or the self-serving representations of those seeking political office or power.