It's very, very close, however unpopular, I have to go with Spiderman. Even though Spawn is quite powerful, I have to hope that good will prevail over Spawn's tapped-darkness.
I kinda don't give a shit about the time travel paradox. It's always been a great story and it's awesome that Skarsgard came back to play Pennywise. The special effects are top notch and I feel like I'm watching a mini hour-long movie every week. If the series is good enough for Stephen King to approve scripts, it's a delight for this Pennywise fan.