Not the part where Steve argues that I'm wrong about the possibility of a Cruz move to the center in the event he was to win the nomination. I'll stand by what I said, but there's no way to know, and he may certainly be correct. We're in the realm of speculation in choosing between "Cruz is what he is, and would only be more so after a successful nomination campaign" compared with "Cruz would be more able to move to the center than Romney/McCain types." And I'll readily concede that reputation (which is what matters here) may be sufficiently sticky that moving to the center wouldn't help even if it happens, and he might be stuck with a reputation for extremism regardless of what he does in the general election.
No, the part I want to respond to is about 1972. I said that a large part of Nixon's landslide was the fundamentals; Steve argues (with links, which I'm not redoing here):
OK, stop right there. Nixon beat McGovern because Nixon was "a popular president during good times"? As Rick Perlstein notes in Nixonland, at the beginning of 1972 Nixon had a 49% approval rating, and the Harris poll showed him beating Ed Muskie by only 1 in a three-way race with George Wallace, who was expected to run as a third-party candidate. Unemployent and inflation had increased significantly in Nixon's first term, as had the crime rate; Perlstein notes that the movies in the theaters -- Dirty Harry, Straw Dogs, The French Connection -- depicted rampant crime. Oh, and the war was still going on, and the country was still racially polarized. No, we weren't happy campers in 1972 reveling in peace and prosperity. We were just sold on the notion that Nixon was the uprightest of citizens holding the line against dirty hippies like George McGovern. That's largely why Nixon rose in the polls throughout 1972 and crushed McGovern.I strongly disagree. It's correct about January 1972; in fact, as I've said, Watergate makes sense in the context of what looked like it might be a close election at that point. But not about November 1972. It was a very good economic year (Nixon was no Carter-like fool; he, like LBJ before him, did everything he could to goose the economy during an election year). The trips to China and the USSR early in the year were major events, and the war was winding down all year, too. That, and not the contrast with McGovern, was surely why Nixon's approval rose in the first half of 1972.
Beyond that, it's not clear that reputation for ideological extremism was McGovern's main problem that year. The Democrats really were fundamentally split; Nixon's sabotage made it worse, but the divisions were real and painful. There's nothing remotely like that on the Republican side right now; there's no significant group or faction that might walk or sit out the campaign if Cruz wins the nomination, so that nominating whoever the GOP '16 version of Muskie or Humphrey would prevent it. And then there's the campaign's troubles beyond ideology, including the chaotic convention and the disaster with the VP slot.
Again: I definitely think that reputation for ideological extremism cost McGovern and Goldwater (and Reagan). But the 1972 and 1964 elections weren't primarily about the out-party candidates,