You're mixing your sports. Three fouls isn't even enough to get you benched. I've got a few more to give....so just wait.

Traditionally, every candidate gets a bump in the polls during and following their convention. It's what happens in a couple weeks that matters more.

Biden is not a great speaker, but he isn't polarizing. The real question is whether or not the group that comes out to vote because the loathe Trump will be greater than the group that comes out to vote because they love Trump. Both sides know that. Trump doesn't have enough support to win unless the group that loathes him stays home. That's not likely to shift, so both sides will be trying to get out their side of the love/loathe equation. That likely means nothing all that much from Biden, and a whole lot from Trump.