WATCH: New Poll Gives Kamala Harris 21-Point Lead Over Trump With Women

While most people take polls with a grain of salt--a small sample group of Americans who still have landlines isn't a perfect indicator of an election outcome, just ask Hillary Clinton--a huge jump in numbers is still a tip-off that a shift is happening.

And right now, that shift is happening with women voters, who overwhelmingly support Vice President Kamala Harris over Donald Trump by a whopping 21-point margin, according to a new poll from NBC News.

The Vice President's favorability has jumped 16 points since she became the Democratic nominee for President in late July. It's the largest increase for any politician since former President George W. Bush’s brief surge in popularity after the 9/11 terrorist attacks.

Vice President Harris also has an advantage over Trump when it comes to being seen as competent and effective, as well as having the mental and physical health to serve as President — a reversal from Trump’s leads on those qualities when he was matched up against President Joe Biden, who is only three years older than Trump.

The poll also shows the increased support for VP Harris from Republicans as she continues to collect endorsements by the hundreds from former GOP White House staffers and others who previously had supported Trump but have grown concerned about his mental decline in the four years since he ran for re-election in 2020.

The enthusiasm for Vice President Harris should last far longer, considering the momentum she and her running mate, Minnesota Governor Tim Walz, have been enjoying for the duration of their campaign.