This is the fallacy some small children have. They think that someday they will catch up and be older than their older brother. Never happen.
Gephardt will always have the lead for length of time in a persistent vegetative state. To beat his record you would have to turn to someone older, like Janet Reno or Helen Thomas.
Finally, apologies to Terri Schiavo, who is NOT in a persistent vegetative state and, unlike Gephardt, might yet recover if she received proper medical attention.