The energy Vice President Kamala Harris has brought to the Democratic Party since President Joe Biden dropped out and endorsed her last month is reportedly spreading to down-ballot races. Politico reported Saturday that Democrats in both the House of Representatives and the U.S. Senate are feeling especially bullish about their chances in November thanks to the momentum Harris has been providing with her ascendancy. While House Democrats in battleground districts were hesitant about tying their brands to Biden, they’re now reportedly vying to have the opportunity to stump with her as they hit …