Even if he does get elected, it isn't a legal cleansing opportunity on his part.

I learned in doing some research last night that Presidential pardon only applies to conviction on Federal charge. Since this bit in New York is on the state level, Presidential pardon cannot be applied. If memory serves, the charges brought in Georgia are also not Federal, so a conviction there would also withstand any attempt to pardon himself if elected.

The other interesting thing is about the actual idea of a President pardoning himself. Although Trump has been very adept at manipulating the justice system, self-pardon is at the least unknown legal ground and is more likely a legally unsound concept. More likely to stand from a legal standpoint would be his getting someone else elected to the office who would then pardon him. Since he is the current candidate and his opposition would hardly consider it, he probably wouldn't be a power in the party long enough (or live long enough for that matter) to set up that scenario.

So, its up to the electorate to decide if there is any dignity left in the office or if this country has indeed devolved into the ethical equivalency of a third-world state, with power hungry madmen doing anything to attain and retain power as a sole reason for existence.