One spoke of carpenters, debt-crushed students and church groups. The other spoke of drones, liberty and debt.

Two of the Republican Party’s leading lights—Florida Sen. Marco Rubio and Kentucky Sen. Rand Paul—brought markedly different messages and styles to the big CPAC stage outside Washington. And both got the most boisterous receptions of the day with back-to-back speeches before a standing-room-only crowd of party faithful.