.NO PRESIDENTIAL argument has possessed as much effect on an election as that between Joe Biden and Donald Trump on June 27th. Mr Biden's performance was therefore devastating that his personal event pushed him to drop out. Due To The Fact That Kamala Harris, the vice-president, replaced him as the Democrats' candidate the ethnicity has actually secured. It is right now a toss-up, according to The Economist's style. On September 10th Ms Harris will certainly deal with Mr Trump in a 2nd governmental debate. How much difference will this set help make?