Option 2 -like many here, I doubt he really has the 'fire in the belly' to run again for the Presidency especially since he and his family are in mourning over the death of his son. Although there is still the outside possibility that he might if only as a matter of duty to safeguard President Barack Obama's legacy achievements with Obamacare and the Iran nuclear deal (among others) in the event Hillary Clinton's candidacy falters.
Is it possible to run a successful campaign half-heartedly?
Would he not do more damage than good by entering the race and running a poor campaign?