Vice Presidents don't do well in elections for the Presidency

Former Vice Presidents don’t do as well at becoming presidents as you might imagine[99]. How to thread the needle of being different to the incumbent and thereby be seen as disloyal, or cowardly for not making these differences clear at the time, or remaining loyal and accepting responsibility for the incumbent’s failings. Kamala was unable to distance herself from Biden in an election where the candidate of change would have an advantage. Biden was unpopular and although history may be kinder to Biden when some of his landmark legislation shows its effect, his approval rating was dismal. Doug Sosnik, a longtime advisor to Bill Clinton said "In general, for a Democratic candidate running in this environment, I think that would be challenging. Then, if you're the vice president of the administration, that makes it even harder."[100]  APVoteCast, a survey of over 120,000 voters nationwide, found that more than half of voters wanted to see substantial change.[101] A CNN exit poll found that voters gave Biden a -19 point approval rating. When Kamala repeatedly stated that she regretted nothing from Biden’s term, she could be commended for loyalty but it was not what voters wanted to hear. Kamala's choice of Tim Waltz as her running mate seemed bold although less savvy than choosing Pennsylvania Governor Josh Shapiro. Walz’s hesitant performance in debates and the liberal record did little to reach out to those who were leaning toward Trump. In fairness, Trump's pick, JD Vance, was widely seen as a disaster. Most commentators agree that running mates neither add nor detract from most campaigns.