No chance of either, as the election is in 2017, not 2018.
In 2017, maybe 1% odds and no, respectively. Can't see any Republican beating Clinton in the scenario where she runs and wins the primary. If there were going to be a Republican who beat de Blasio, it would have to be someone as far away from Donald Trump as possible (and would still require de Blasio's various slightly murky scandals getting significantly worse), not Ivanka. I'm not aware of any plausible Republican candidates who stand a greater than 5% chance of winning against de Blasio. The bench in NYC is understandably extremely weak.
Raymond Kelly or Tom Allon?