The third sign of change is the immense audiences for the two Republican debates, and not just for Fox (24 million), but also CNN (23 million). The previous high, for the Democrats’ close contest in January 2008, was 8 million. That was followed by the highest primary turnout in history, 37 million for Democrats, compared to 21 million for Republicans, and to a turnout surge among blacks and young people that gave the Democratic nominee the biggest percentage victory margin since 1988.

Maybe that high viewership only represents celebrity gawkers tuning in to watch Trump. But maybe it also represents, at a moment of high discontent with incumbents and institutions, a curiosity as to whether Republicans can provide an appropriately disruptive alternative. We’ll see whether the first Democratic debate draws as big an audience Oct. 13.

If the Republican primary electorate expands as vastly as the Democrats’ did, all the old rules about how to win may prove obsolete. New voters looking to upset the applecart (or tear down the temple’s columns) may overshadow the suburban economic conservatives who favored Mitt Romney or the non-metropolitan religious conservatives who favored Rick Santorum in 2012.