Kamala Harris...

Because the Democratic party is a joke

"She is not Trump" is not a valid answer.

Seems pretty valid to me.
She does not have the mental issues Trump has - acute narcissism and psychotic inability to see reality leading to inability to distinguish facts from his imagination.

But in addition to that , she's not Biden - ie under 60 and does not give the impression of senility.

Answer is simple. President Joe Biden picked her off the Senate to be his running mate in 2020, even after she attacked him in the primary for having a perceived race problem with electability. He mentored her procedurally while she mentored him culturally. They have been a terrific and victorious team ever since. They’ve particularly excelled when it comes to working with Congress due to their combined legislative experience and networking.

If it weren’t for his age and the presence of a reality show demogogue with a cult behind him opposing him, President Joe Biden would have easily earned a second term based on his performance and accomplishments alone—and also for his curtailing of any disaster and scandal. He's not an isolationist, but he still puts America First. With this in mind, it's natural to respect and receive his endorsement of his Vice President with swift validation and much enthusiasm for her to show us what she's learned and prosecute the case against her cognitively-declined rapist-felon Republican nominated (!) opponent, and his out-of-touch, Yale-educated elitist babyface running mate. (The one who hasn't had a mob of Trump cultists try to lynch him yet.)

American Carnage is on the ballot. Either we have it with Trump... or we avoid it with the level-headed Kamala Harris. VOTE November 5th!

Because she isn't the "Project 2025" candidate and that's as good of a valid answer as any.