You don’t think Hitler was elected? Because that was their point. Regardless of the broader forces at work, how is it not the responsibility of the electorate to elect the right government?
I do not believe he was attempting to blame anybody though. In my view, he is warning us ( well, Americans — I am not one ). He is saying that there is one chance to defend the future and, if you do not take it, you may be denied another opportunity.
That’s not quite true. The NSDAP did get the largest percentage of the vote, just not the absolute majority. So they needed other parties to form a coalition for a government. The conservative party and their figurehead Von Hindenburg made that move thinking they could control the Nazis this way.
Hitler still won the election, democratically (although their thugs did intimidate a lot of people to vote for them).