ISIS is in trouble. They want to persuade Obama to get the Russians off their backs.
So they make him an offer he can’t refuse: “If you don’t make the attacks against us stop, we will ensure that no Democrat will win in November”.
They figure that Trump is more likely to just withdraw from Afghanistan and the Middle East, and not spend American resources “promoting democracy” there.
Problem with that logic is I don’t see Trump pressuring the Russians to back-off for any reason. If anything he seems appreciative of Putin.