In the aftermath of the stunning upset victory of Ronald Reagan in 1980 Americans were asked whether they thought of themselves as “liberal,” “moderate,” or “conservative.” The “liberal” designation drew 18%, while more than twice that number (37%) claimed the title “conservative.” This was consistent with the conservative sweep, up and down the ticket, that characterized the 1980 elections. The preponderance of conservative over liberal self-designations was much the same in 1984, when Reagan was reelected; in 1988, when his vice president, George H. W. Bush, succeeded him in office; and in 2000 and 2004, when the younger Bush was elected and reelected. When conservatism predominates, as expected, conservative candidates win.

But what is not expected is that conservative self-identification also predominates – the numbers are in fact quite similar – when liberals win, as in 1976 (Jimmy Carter), 1992 and 1996 (Bill Clinton), and 2008 (Barack Obama). In the election of Barack Obama in 2008 there were a few more liberals (20%) and slightly fewer conservatives (35%), but had ideological self-identification driven that election outcome, John McCain would have won by historic numbers. In fact, if identification were the driver, all presidential elections of the era in which we have measures of ideological self-identification would have been Republican landslides. In the modern era, that is, conservative predominance in matters of self-designation is more a constant than a variable. An explanation for the predominance clearly is needed.