It's because Pence would not have ever had a chance. Trump is probably the only one who could have polled this close to Clinton. Clinton over the past 8 years has become the heir apparent to the throne. Sure Pence probably would be a better prez than anyone, but no politician could have a chance at beating hillary. Just like Jim Webb would have been a much better candidate than hillary, but he has no curb appeal. No one really likes hillary, but she has been running for president for 30 years, its hard to overcome that. Only an entertainer and shocking loud mouth could have a shot at it.
I don't want Clinton to be president, she is a committed leftist who serves a master that is nefarious in nature. I don't know who it is, but it ain't good.