The vice-president’s thankless portfolio is more to blame for her slip in political traction than staff turnover. Her popularity started sinking when she first visited Central America and appeared dismissive of a suggestion that she visit the border. Behind the scenes, she was worried the assignment to take on the migrant crisis was a clear political loser. When critics latched on to her admonition to would-be migrants — “Do not come” — her frustration grew, as this was the administration line. Later, she remained silent at a tense meeting with Biden, letting other officials speak when he asked for updates. Afterward, she told aides to underscore that she was focused on the origins of migration, not the border itself. Her other top priority — voting rights — was no less publicly frustrating when the administration’s preferred legislation predictably failed in the split Senate. Some close to her wonder why she didn’t muscle her way into leading more popular projects: implementation of the COVID-relief-bill spending or, later, the infrastructure package.

Most exasperating to her advocates, however, have been the questions about her preparedness for the top job, an especially sensitive line of inquiry ever since the 79-year-old Biden contracted COVID earlier in July. The concern comes mostly from her occasionally stumbling responses to journalists. She told a CBS interviewer who asked if Democrats had erred in not codifying Roe v. Wade into law, “I think that, to be very honest with you, I — I do believe that we should have rightly believed, but we certainly believe, that certain issues are just settled. Certain issues are just settled.” It was one genuinely cringeworthy moment in a straightforward interview, but it was shared far and wide, especially on the left. “Often Democrats are their own worst fucking enemies,” said Democratic pollster Cornell Belcher. “Democrats will stab each other up at the drop of a dime.”