NBC: A double-digit increase in popularity, rising Democratic enthusiasm and an early edge for representing “change” have vaulted Vice President Kamala Harris forward and reshuffled the 2024 presidential contest, according to a new national NBC News poll. With just over six weeks until Election Day, the poll finds Harris with a 5-point lead over former President Donald Trump among registered voters, 49% to 44%. While that result is within the margin of error, it’s a clear shift from July’s poll, when Trump was ahead by 2 points before President Joe Biden’s exit. Kamala’s favorability has jumped 16 points since July, “the largest increase for any politician in NBC News polling since then-President George W. Bush’s standing surged after the 9/11 terrorist attacks.” Harris also holds the advantage over Trump on being seen as competent and effective, as well as on having the mental and physical health to be president — a reversal from Trump’s leads on those qualities when he was matched up against Biden. And in a contest between a sitting vice president and an ex-president, featuring an electorate that overwhelmingly thinks the U.S. is “on the wrong track,” Harris has the upper hand on which candidate better represents change and which candidate can get the country headed in the right direction. That last is because we feel like we’ve been forced to deal with Orange Julius Caesar for at least a century. A little tidbit: In an expanded ballot with third-party candidates, Harris leads Trump by 6 points, 47% to 41% — with Robert F. Kennedy Jr. at 2%,…