Just to be clear, the constitution only prevents electors from voting for both Pres and Vice President from the same state.  They cast the votes separately.  Now there's certainly ways around this.  Jeb could register in another state if he chose to choose Rubio (such as Texas).  Much like Cheney chose to register in another state when he ran with Bush II.

 

In smaller states, it wouldn't even really matter.  Though in a large state like Florida or Texas it might.  But even then the vote would eventually go to the senate, and Republicans currently have a majority in the senate.


So the constitution definitely does allow people from the same state on the same ticket.  All it does is prevent electors from voting for two people from the same state.  And again this is easily gotten around by registering in a different state.  Bush/Rubio is certainly possible.  

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