Despite what everyone else is saying yes you could run them in parallel just fine. Series and Parallel are different. You can accomplish running them in Parallel with one single wire. Just be sure that first of all you know what your doing with the wiring because its easy to get them crossed and then goodbye reciever. And make sure both sets of speakers are 8ohm speakers. If you dont kjnow how to wire them in parallel perhaps someone else will draw you a diagram. Also. Make sure your speaker wire is at least 14 gauge.
Im pretty certain the Denon has B speaker outputs why not just use them?
But I dont know why you would want to run them both at the same time unless you think it sounds better.