“The casino does not always win,” Stuart Stevens, Mitt Romney’s lead strategist during the 2012 campaign, quipped to me in September. “But that’s the way to bet.” The casino won in 2012, and will very likely win again in 2016.

And yet already, Trump has destroyed one elite-favored presidential candidacy, Scott Walker’s, and crippled two others, Jeb Bush’s and Chris Christie’s. He has thrown into disarray the party’s post-2012 comeback strategy, and pulled into the center of national discussion issues and constituencies long relegated to the margins.

Something has changed in American politics since the Great Recession. The old slogans ring hollow. The insurgent candidates are less absurd, the orthodox candidates more vulnerable. The GOP donor elite planned a dynastic restoration in 2016. Instead, it triggered an internal class war.

The contest for the presidency turns on external events as much as—or more than—internal party politics. George W. Bush’s team believed that the last-minute revelation of a 1976 drunk-driving arrest cost him the popular vote in the 2000 election. Jimmy Carter blamed his 1980 defeat on the debacle of the attempted rescue of American hostages in Iran. So anything can happen. But that does not mean anything will happen. Barring shocks, presidential elections turn on the fundamentals of economics, demography, and ideology.