I recently did this and had two utility bills. But two isn't accepted so I was given an affidavit form where I wrote down that I was who I claimed to be.
It was pretty ridiculous. I already had a passport, other state DL, SSN, and birth certificate. The points for proof of residence are the dumbest part of RealID.
Someone I knew had some rigamarole to get their kid his first license because he didn't have any utility bills or whatever to prove his address. :-/
There's this weird thing that de facto you need state residency and a permanent address to live "normally," have government ID, etc. but there's not AFAIK any actual specific legal requirement to have same.