Although it's pretty equal due to all three having an impact on my existence, I've decided it was Alexander the Great that has had the most influence in MY LIFE.
Why? Because MY LIFE started out in a typical protestant Christian way, so it started out heavily influenced by Jesus of Nazereth. However, I soon became a big fan of history, and my favorite historical empire became the Mongols once I learned about the sheer size of their conquered territory, so Genghis would have had a lot of influence then. That was back in high school, though, and though I still play as the Mongols when I drag out and dust off "Age of Empires II", I am currently drawn to read the posts here about Alexander. Therefore, Alexander has the most influence in MY LIFE, because the others are largely forgotten. Only about 10% of me remembers Jesus, and maybe 20% Genghis. I'd say at least 40-50% of me remembers Alexander, and I'm typing more about Alexander right now, at this instant, so he wins.