I foresee a hung electoral college where no candidate has an overall majority, and that will be used as an excuse for electoral votes for the other Republican to be transferred to Trump giving him a majority.
I don't think this can legally happen. This situation is described in Amendment XII to the Constitution:
The person having the greatest number of votes for President, shall be the President, if such number be a majority of the whole number of Electors appointed; and if no person have such majority, then from the persons having the highest numbers not exceeding three on the list of those voted for as President, the House of Representatives shall choose immediately, by ballot, the President.
So if no candidate gets over half the electoral votes, then it goes to the House, who selects by vote the President from the two or three candidates who got the most electoral votes. Each state gets one vote in that process, and the winner must get more than 50% of the votes cast in the House. If the House can't select a President by March 4 following the election, then the Vice-President acts as President until a "real" President can be chosen. It doesn't say anything about multiple swipes at the Electoral College vote with vote-swapping until someone wins; if I'm reading it right, if the first vote fails, it goes straight to the House.
