When exactly are we talking about? If we're talking about Pre-Mongol, not the slightest chance, only with an enormous power vacuum opening up in Eastern Europe that all the remaining powers are too far away from to access. Mongol and/or Post-Mongol are more likely, if still barely possible. Maybe it goes the Constantius route, or the Golden Horde somehow defeats Moscow and all the other rebelling cities, or the original Mongols decide to raze all the important cities when they first invade, etc.
Something a little more likely is that Novgorodian trade ends up far more successful than in OTL, leading them to fully dominate the Baltic, leading them to eclipse Moscow after it rises, leading them to eventually defeat it.