.NO PRESIDENTIAL DEBATE has had as a lot effect on a vote-casting as that between Joe Biden and Donald Trump on June 27th. Mr Biden's performance was thus devastating that his very own party pushed him to quit. Since Kamala Harris, the vice-president, replaced him as the Democrats' candidate the ethnicity has tightened up. It is actually now a toss-up, according to The Economist's style. On September 10th Microsoft Harris will definitely deal with Mr Trump in a 2nd presidential argument. How much distinction will this produce?