Thursday night’s GOP primary debate in Cleveland was not only the most watched presidential primary debate ever, it was “the most watched cable news program” in history, with 24 million viewers tuning in, according to AdWeek. This compares to 3.3 million viewers for the first Republican debate in 2012, and 2.1 million for the first Republican debate of 2008.The obvious explanation for this extraordinary number of viewers is of course the red-haired celebrity who stood at the center of stage. But the Donald alone probably cannot account for the huge audience—after all, 6.1 million people watched the minor league GOP debate, featuring the lower-rated contenders, at 5 p.m. To repeat: almost three times as many people watched an event featuring candidates like Jim Gilmore and George Pataki in 2015 than watched an event featuring John McCain and Mitt Romney in 2007.One reason for the tremendous interest was probably that Fox News put on a different kind of event from anything we have seen before. This was “the first 21st century Presidential debate“—more than its predecessors, it favored sharp questions and pithy answers, and emphasized style as well as policy substance. Candidates had to be savvy as well as theatrical, and embrace the reality television format. This is the direction our politics is heading, like it or not—and it may in fact be quite successful at boosting political engagement.Indeed, given the magnitude of the increase in audience size, it is also hard to avoid the conclusion that people are simply more excited about politics, and the young, diverse, and unpredictable Republican field in particular—perhaps partly as a result of the stylistic change described above. We have been treated to countless stories over the years about how young people are politically disengaged, and contaminating the rest of the country with their apathy. But according to data from CNN, the debate audience hardly resembled the retirement community that is Fox News’ staple—”of the 24 million viewers, 7.9 million were in the key advertising demographic of 25 to 54 year olds.”The debate numbers are a good signal for political engagement. It will be interesting to see if the candidates can keep them up.