And I've got a Mana Denial Wizard that focuses on that strategy nearly exclusively. It's so annoying to play against that I don't even like playing it, but it has been quite successful. When it takes your opponent 2-3 rounds to channel enough mana to remove a Ghoul Rot, you know they're not having a good day. Oh, it does use the Gate to Voltarii, but no Gorgon Archers, as it prefers Mana Worms, Mana Leeches, a Devouring Jelly and a Gargoyle.
And I've been playing against an Undo Wizard who has enough Dissolve/Dispel and Attack spells to undo anything you try to do, then sticks some DoT with Arcane Ward / Enchanter's Wardstone and watches you die a slow death (but can be accelerated through lightning). No Gate to Voltarii in this one.
A well-played Paladin could win against either of these Wizards, I'd assume. Pillar of Righteous Flame could take out a Mana Worm swarm with a little assistance, and a Paladin has enough healing to survive DoT for quite a while, during which time hopefully he can get some damage through. He needs at least a couple creatures, though, as the first melee attack each round is going to be mostly neutralized by the Voltaric Shield.