In a world where Corbyn got 40% of the vote, anything is possible. While he may not be the average joe, many people appear to like authenticity, the perceived intelligence and the fact that he appears to believe in something ideologically.
Personally i think we need a Cameron who is a bit more socially liberal and a bit more aggressive on tax and spend while retaining a strong pragmatic streak on areas like housing (the private sector cannot deliver the amount we need) and that a traditional Tory like Mogg would be somewhat limited in appeal.
With all that being said, my thoughts were primarily true pre-2015. In a world where Corbyn is Labour leader and the third parties have collapsed, there is much more latitude on both the left and the right for leaders to take more extreme positions without being damaged (because the other leader takes a fairly extreme position the other way) so perhaps Mogg could get some of those 2015 Tories back on side while keeping the Corbyn factor strong enough to prevent many lost votes.
At any rate, he's not my first choice for Tory leader.