.NO PRESIDENTIAL controversy has had as much effect on a vote-casting as that between Joe Biden and Donald Trump on June 27th. Mr Biden's performance was actually thus disastrous that his personal party pushed him to leave. Given That Kamala Harris, the vice-president, substituted him as the Democrats' candidate the race has secured. It is actually now a toss-up, depending on to The Financial expert's version. On September 10th Ms Harris will experience Mr Trump in a second presidential controversy. How much difference will this make?