Married yes, practicing(tm) polly yes, if not actively poly at present
Happily married here, and honestly for myself not even really looking.
Won't say I couldn't love somebody else, but no desire to seek out more...
However wife, when I met her told me she knew there was a female soul mate out there, even before we realized there was anything more to us, then me be a friend to her brother.
While I still think fears of losing me, and 'its wrong' cause her to hold back; she also some times directly sometimes more subtely does make it clear she does crave female companionship.
So I would still say 'practicing' poly right now, even if its just encouraging wife it would be ok, it is normal, and helping her figure out what she really wants, and have the courage to try.