Vice President Kamala Harris has closed the enthusiasm gap with former President Trump as Democratic confidence surges in the wake of their Chicago convention, according to a new poll.The USA Today/Suffolk University poll found Harris leading Trump 48% to 43% among likely voters, a lead that lies within the poll's margin of error.The swing toward Democrats also held true down ballot in the poll, with 48% of likely voters saying they planned to vote for the Democratic candidate in their local congressional election, compared to 43% for Republicans. That represents a seven-point swing from earlier this year, when Republicans held