"Neither the Constitution nor the Electoral College prevents Bush from picking a fellow Floridian or any candidate from choosing a running mate from the same state."
There is not a short quick answer to this.
It takes time to explain the procedures of the electoral college, and how electors vote separately and distinctly for presidents and vice presidents, and how they cannot vote for both a president and vice president from their own state.
Because it gets complicated, many people often say that the President and Vice President cannot be from the same state.
As a practical matter you will never see a presidential ticket with both candidates from the same state.
The Constitution does not prevent it, but it creates a problem. If both candidates come from the same state and they win their home state, the electors can cast their votes for the presidential candidate or for the vice-presidential candidate, but not for both. It could create a case where you have a president from one party and a vice president from the other party.