What happens if both players have only 3 cards in their library and I cast Wheel of Fortune (Each player discards his/her hand and draws seven cards) ?
Is it any different if one player has 1 card and the other player has 3 ?
Here are the relevant Comprehensive Rules:
Nothing happens until a player would get priority, so the order in which the players drew the cards doesn't matter.
All the SBAs are performed simultaneously.
All the players would lose simultaneously if it were not for the following exception:
In both cases, the game ends in a draw. Because the rules pay no attention to what's happening during the spell's resolution, having more cards doesn't protect you in this case. As soon as state-based actions are checked (i.e. after the spell resolves) you both lose the game at the same time and it's therefore a draw.