Vice President Kamala Harris and President Joe Biden at the White House.Chip Somodevilla/Getty ImagesBiden's less-than-stellar debate performance against Trump set off alarms among many Democrats.It also shined a light on the party's past struggles in building a farm team of future leaders.The debate will likely push Democrats to rethink how power is transferred to younger generations.After President Joe Biden's middling debate performance Thursday night, many Democrats began to panic.With voters already on the fence about Biden's readiness for a second term due to concerns over his advanced age, party leaders wanted the president to use the debate to not only reassure the electorate but also make an impression that could turn the race in his favor.But that didn't happen.