More of an extended comment, than a properly sourced answer:
There is an implicit contradiction in the article that you mentioned:
Consider a left leaning US voter who is wondering whether to vote for Sanders or Clinton. She thinks Sanders is the candidate who best represents her worldview and wants to vote for him even though she knows he has little chances of winning. Her Pro-Clinton friend uses the utilitarian logic presented in the article you linked to argue that she would be ethically wrong in doing so, since the consequence of supporting Sanders no matter what will be to increase the likelihood of Trump winning. So it seems that the consequentialist approach (voting for an outcome) would be to support Clinton, while the deontological approach (voting on principle) would be to support Sanders.
But then the Clinton supporter is contradicting herself here: The desired consequentialist outcome - preventing Trump from winning - is itself based on deontological reasoning. Why is the desired outcome here preventing Trump from being president? Because his is a mysoginist, a racist bigot, etc...and someone like that should never be president - so essentially a deontological rule about what views a president should be allowed to hold.
This could also be applied to the GOP in general (not just Trump): Why should a democrat prevent a GOP administration at all cost? because they think people are more important than corporations, that the environment takes precedent over big oil, because they are pro-choice, pro-women's rights, because they think religion and state shouldn't mix, etc....
So ultimately the choice comes down to voting for principles, not outcomes, anyway.
This points to a more general flaw in the article: The moment you are voting for a person or a party, the only way you can decide your vote is deontological. You are choosing a person or a party because you have a shared set of principles with them. You do not know before hand how they are going to manage the country, and you definitely don't know what the various outcomes of their administration will be. All you know is that they believe in a certain number of political and economic principles.
Moreover claiming to vote based on utilitarian principles (as one of the professors quoted in the article says) is in a sense disingenuous: we don't know what the majority wants until after the vote had been tallied, that is the whole purpose of voting, so how can we claim to be voting to maximize the greatest good or the greatest happiness?
The way I see it, the only way that a case be made for voting based on consequences as opposed to voting based on principles, is if the vote is on a particular outcome, not a person or a party, as was the case with the Brexit vote.
In such a situation, it might be possible to argue that people knew before hand what the likely consequences of the UK exiting the E.U was, and if they voted on principle even though they new that the economic consequences for the U.K were bad, then one can accuse them of being immoral by failing to take into account the negative consequences of their actions.