When Richard Nixon won the presidency, the silent majority of Americans was white and conservative. The demographics of this country have changed, and that change is now accelerating. Voters are getting younger, more racially diverse, and less tied to organized religion. Sarah Palin's base is uneducated and theocratic. She is incapable of expanding her appeal beyond that shrinking base.
In 1965, when he successfully passed the Civil Rights and Voting Rights Acts, President Johnson told aides that he had lost the south for the Democrats for a generation. Until then, many white conservative southerners had remained Democrats. A century later, they still couldn't vote for the party that had sent Abraham Lincoln to the White House. By the end of the Reagan era, most had become Republicans. No such future split is in the offing for the Democratic Party.
In 1968, the Tet Offensive had shattered the illusion that the Vietnam War somehow was "winnable." The late great Walter Cronkite had said so. President Johnson had told aides that having lost Cronkite, he had lost the country. He was right. The war was his. The war was his party's. His run for re-election was destroyed by a little-known Minnesota Senator. The best Democratic candidate was yet to enter the race. On the night that candidate took control of the race, he was assassinated. The 1968 Democratic Convention was torn apart by the war. The television-watching public saw turmoil within and riots without. That convention ended up nominating the defeated President Johnson's Vice President. For Richard Nixon, it was a political perfect storm, blowing to his every advantage. And he still barely managed to win.
Despite his moral vacuity, Richard Nixon was smart and articulate. Those who heard, but didn't see, his 1960 presidential debate with John F. Kennedy thought he had won it. The polls showed the vast majority of the public thought Sarah Palin was destroyed in her debate with Joe Biden. Sarah Palin never will be confused with smart and articulate.
Richard Nixon had been President Eisenhower's Vice President. Sarah Palin helped sink John McCain's presidential ambitions. You never get a second chance to make a first impression. Sarah Palin can go on all the talk shows and book tours she likes. She still will be Sarah Palin.
Richard Nixon had survived a potentially career destroying scandal with his famous "Checkers" speech. He had survived by going straight to the public. Every time Sarah Palin speaks in public, her approval rating tanks.
In the 1960 presidential race, Richard Nixon almost beat John F. Kennedy. For president. He already was widely known. He already had an established base. Sarah Palin never has won a national political race. She never has come close. She never has won the public. She never will.