Still, some Democrats are beginning to worry that her sluggish approval numbers are indicative of a bigger problem for Harris, who as vice president ranks as the party's potential heir to Biden, the oldest president in U.S. history at 78. They have many of the same doubts that have long dogged her, and contributed to her failed campaign for Democrats' 2020 presidential nomination — about her style, political instincts and treatment of staff... A recent YouGov poll showed some of the factors behind the numbers. Biden did better than Harris among white voters across the board, but especially among white women with college degrees. While both get high approval from Democrats and low approval from Republicans, the intensity of support or opposition is different: More Democrats said they "strongly approve" of Biden than said the same about Harris, and fewer Republicans said they "strongly disapprove" of him. Those differences reflect on the one hand Harris' lukewarm support from the Democratic Party's base, a problem since the 2020 presidential nomination race, and on the other the relentless attacks against her from conservative politicians and media.