This sounds too much like second-chance voting to me. And I’ll bet those supporting it have already figured out how to game the system.
My biggest fear is that this will be used to allow marginal career politicians to keep their job, while at the same time turning competition into an advantage. Here’s how I see it working for this purpose:
For argument purposes, and to avoid partisan accusations, we’ll call our political parties “up” and “down” rather than “left” and “right” (but not necessarily in that order!). Say that your “down” candidate is an unpopular, incumbent moron that no one likes, but who is too powerful to deny a place in the race. Running as the lone candidate for your party, however, will not energize the party base and will likely result in lower turnout. Let’s say that in a full-turnout match that the “down” party has a clear 55/45 advantage. Let’s also say also that about 30% of the “down” base will simply stay home on election day rather than vote for the moron, giving the “up” party a 45% to 38.5% win.
Say as a hedge you run another candidate from the “down” party in addition to the incumbent. They can’t win, but they are selected because they appeal to the voters who would likely stay home rather than vote for the moron. However, since they are voting anyway (and since they are rabid “down” party members who would rather kill themselves than vote for an “up” candidate), they rank the other “down” party candidate (the moron) as their second choice. Now, when neither party gets a 50% majority, the “down” party incumbent acquires the votes from the 2nd “down” party candidate, thereby pulling a rabbit from the hat and netting a 55-45 win. Note that the incumbent didn’t win because he was the most popular, but instead because the party base was energized to vote (for someone else!) resulting in a higher turnout.
Only fives minutes in and I’ve already figured out one way to game the system. I wonder how long it will take the professionals?.