I don't see a whole lot of difference.
...although I have concerns about this as possibly not being Constitutional.
How?
I see it as an unfair application of election laws. If such a system is permitted in Maine, where a candidate “must” receive 50%+1 for a federal race, but doesn’t happen in another state, I see this as an unequal and unique situation. Either all should have it, or none. However, I do not support this at all. There should be a separate runoff election, not an “instant” one.
Also, there is the issue that someone is technically casting MORE than one vote for one single office. In fact, this gives disproportionate power to 3rd party voters. You know your candidate isn’t going to win, so you can cast a 2nd ranked vote, presumably for a D or R. What if you wish your 2nd (or 3rd) ranked votes to go to the SAME candidate, so you’re casting two or three votes for the same person, which you aren’t permitted to do ? The whole thing is ridiculous and rife for fraud.