Taken together, the assumptions behind these methods make it almost impossible to compare today’s candidates to Goldwater in any meaningful sense: How do you compare the ideology of a modern candidate to someone who thought battlefield commanders should be allowed to use tactical nuclear weapons without presidential authorization, or who never had to take a position on abortion or gay rights (when he did, Goldwater was actually to the left of most modern GOP candidates)?

But even if we were to concede that Walker would be the most conservative nominee since Goldwater, we’re left wondering, “What does it matter?” Remember, political science also teaches us that Barry Goldwater (like George McGovern) didn’t really lose because he was too extreme; he lost because Lyndon Johnson was in his honeymoon phase and the economy was growing smartly. Bob Dole (CFscore of .6, pre-nomination) was closer to the center (assuming a center of somewhere around zero) than Bill Clinton (CFscore of -.899). George H.W. Bush (CFscore of .795) is as far right of center as Michael Dukakis (-.839) is left.  

Perhaps most tellingly, the most extreme nominee under these scores (which only date back to 1980) is Barack Obama, whose pre-nomination score of -1.35 is farther to the left than John McCain’s (.68), Romney’s (.878) or Walker’s (1.28) are to the right. Obama’s post-nomination score (-1.65) is twice as far away from Clinton’s post-nomination score (-.98) than Walker’s is from George W. Bush’s (1.04).