When Boehner began his career as a legislator, in Ohio’s State Assembly, Cruz was a teenage ideologue — a whiz kid member of the “Free Enterprise Institute” in Houston, where they studied conservative giants like Milton Friedman and Friedrich Hayek the way rabbinical students tackle the Talmud. He was a student at Princeton and then Harvard Law School when Boehner was the fourth-ranking House Republican.

“The institutional contrast between Cruz and Speaker Boehner is stunning,” said congressional scholar Sarah Binder, of George Washington University and the Brookings Institution. “The upstart Cruz who builds his power on the outside and pressures those within versus Boehner who built his power from within the institution — as both committee and party leader.  At the end of the day, Boehner has been a lawmaker at heart …. We don’t really use the old ‘work horse v. showhorse’ distinction across lawmakers anymore, but it seems apt in a way to tap the differences between Boehner and Cruz,” she said in an e-mail interview with The Washington Post.

To be sure, Boehner was having trouble controlling his conference before Cruz was elected to the Senate in 2012. And Cruz did not humiliate and ultimately topple Boehner on his own. He had plenty of tea party conservatives in the House helping him out, not to mention the tea party movement itself and the Heritage Foundation. Indeed, the dynamics that drove Boehner from office had been building for some time, accelerating with the election of President Obama in 2008, who became the chief target and rallying point for the growth of the grassroots on the far right.

Yet no single conservative in the House had galvanized and excited conservative opinion as had Cruz in the summer and fall of 2013. His relentless crusade whipped up tea party activists who made it clear that compromise would have consequences for Republicans.