"If the Russians influenced 1% of the population to vote for Trump, that was far more than enough." So says a person identifying himself as GaryO from Virginia Beach, Virginia, in the comments under a news story in the Deseret News.
As I read it, I find myself wondering if (and doubting that) there have been any surveys asking voters if they were influenced. Yes, they might not admit to it, and they might not know enough about the fake stories, etc., to know if they were influenced. Still, you could present the survey as best you could and make an effort to determine if the Russians did, in fact, poison the pond -- did successfully change the election.
One approach to the survey would be to query those just those who were undecided and those who changed their minds at the end, asking them if they remember what factors persuaded them to vote the way they did.
It would be a late survey, but a late one is better than none at all. And, it would be better to do it now than a year from now. The questions about this election are going to be hanging in the air and haunting us for decades to come, so the more we can determine this close to the event, the better.