President Joe Biden has a tough task in his immediate path forward to dispel Democratic fears about his health, wrote Stephen Collison for CNN on Wednesday. The developments following last Thursday’s debate, he wrote, have “created another extraordinary twist in a stunning campaign featuring two presidents, one who is a convicted felon, and the other who is already the oldest to hold the job in history” and give Trump — who ironically is also advanced in age and facing questions about his mental acuity — an opening to shift the focus away from the contrast of competency and leadership that Bid…