I'm looking to setup a timing system for my Pedal Prix team (like car racing with drivers changing, only with "recumbent" (sort-of laying down) bicycles, and here is my current setup:

RFID Reader to ID the rider, connected to an XBee at 9600 Baud

GPS (to identify crossing the lap line) connected to another XBee at 115200 Baud (probably 115200).

I then obviously need 2 XBee receivers, and I'd like to connect both of these to one Raspberry Pi (both on GPIO pins if possible). (Arduinos and Pis draw too much current to be in the vehicle, and/or are superfluous to our needs.) Is this possible?