The 2016 Republican primary was at an inflection point on the eve of the CBS News presidential debate in Greenville, South Carolina. Then-candidate Donald Trump had just won New Hampshire decisively. National polling showed him leading the field by 8 points. A victory for Trump in the Palmetto State would make his nomination all-but inevitable.

Trump, a streetwise New Yorker who lobbed insults and went off script at rallies that resembled tent revivals, shattered the GOP’s staid conservative mold. His push for a border wall and mass deportations challenged the party’s embrace of comprehensive immigration reform. His rejection of trade deals and globalization bucked the Republican commitment to free markets. And his scorn for interventionist wars defied the GOP’s neoconservative wing, upending decades of predominance.