Not a huge one, they still reside within one league, but Mace is the definite superior.
His showing with Palpatine is taken as an "amp", but people forget that he wasn't amped by any external power. It was a thing he had in him, his own power, just on a scale he never mastered/realized to channel it fully beyond that one specific day, and given it was his peak mental state he could ever reach, I doubt he would ever reach anything close to it.
He's also not the guy that boasts insane telekinetical damage output, he's more akin to Obi-Wan type guys. His level of reflexes, absurdish physical feats, are better in the physical area, than Dooku's feats are in the telekinetic area, if you get what I mean. Pretty much Dooku demonstrates his power in telekinesis and Lightning - his feats in that area are impressive. Still, Windu's power demonstrations in the physical area should translate to an even greater power, but that's something you can never truly gauge.
Eh, I would guess that in actual combat Windu would demonstrate real superiority, but not the one you can plainly see with the second side being visibly inferior. And - it's like most fights really go, unless somebody holds an incredibly clear edge, fighting is just random as hell. I would imagine their fight would look like Obi-Wan vs. Ventress. I mean, we have no doubt that Obi-Wan would win in the end, but there is no visible overpowering. Yeah, Obi-Asajj would be a good example, I guess.