The value of debates
After this weekend's debate, it's understandable if some people want to give up on the format entirely. Do debates matter? They would appear to this year: Trump's fall in the polls began with his disastrous first debate performance, and after Sunday night some undecided voters shared how the televised encounter helped them make up their minds.
Even if Trump's candidacy is a little extreme, two thirds of voters told Pew during the last election the debates were helpful in determining their vote.
In the very first live TV debate JFK used his telegenic presence to charm Nixon voters all the way to the White House.