US Election: can Kamala Harris gain momentum in the swing states?

It’s less than two months since Joe Biden ambled onto a debate stage and delivered a disastrous performance that would ultimately end a 52-year career in politics.
Tonight he says goodbye, not to the presidency, yet, but the spotlight as he seeks to shift attention onto Kamala Harris.
Once his unpopular Vice President, Harris is now leading in some polls and has dramatically changed the mood within her party. But it’s not the Democrat faithful in this convention centre who need to be convinced.
Like most presidential elections, the polls say this one will be decided by razor thin margins in a handful of swing states, and both parties are busy canvassing to attract the precious few undecided voters.