A lot of people when voting consider what the person they vote for will do for them politically rather than what they are like personally. They might prefer a good person in office, but in the end a good person who pushes policy they don't like is probably not going to win over a shit who does things they feel are politically effective.
And in many cases they don't like either option much personally, so it's even less compelling what they think about their morals.
While some would argue a person whose morals in his or her personal life is questionable will also be a questionable political leader, in reality I don't think that always holds true, and many people see that. Some people are even very upright in their political life, but not great in their love life, or with their kids, etc.
Some people also will think the allegations are false. And as for the comments about celebrity meaning women let men do what they want, nasty as it is there is some truth to it. Of course lots don't and I think most are aware of that. But when people react as if that is unthinkable, it tends to make them look like they are more concerned with saying what they'd like to be true than what is true. Lots of Trump voters find that kind of thing tiresome.
But I would also say, you can't understand Trump voters without understanding the left in the US, and how they are perceived by Americans. They see them as completely out of touch with reality, spouting dangerous ideologies, despising the working classes, as hating their own country, as authoritarian, and worse.
They see both the Democrats and traditional Republicans as being there mainly for banks and the rich. This is something I think people in the UK sometimes miss - the Democrats aren't generally socialists. Hilary Clinton was seen as a big business, pro-bank candidate, and that's true of most Democrats. Remember that they rejected Sanders twice and a lot of people who would have preferred him either refrained from voting at all, or they voted for Trump, because they talked about a lot of the same things.