Let's use the EU over there to figure out all of their force powers/abilities at the time and figure out how they would fare in a duel with each other. Jedi Anakin from ROTS (a light side anakin, before he turned to the darkside, while he was still a good guy in the beggining-middle of the movie, before turning to the darkside in the chancellor's office).

Obviously, without the darkside, anakin's force powers are different.

Using the EU, let's figure out what of all of Anakin's force powers were while he was on the light side in ROTS, and what Sidious's force powers were, and let's compare them, to see who would most likely win the fight.

Honestly, i think Anakin has a greater chance to win the fight, and, at least there's a 50/50 chance.