Married, yes, practicing(tm) poly, yes, if not actively poly at present
Happily married here, and honestly, I am not even really looking.
I won't say I couldn't love somebody else, but have no desire to seek out more.
However, when I met my wife, she told me she knew there was a female soul mate out there, even before we realized there was anything more to us than me being a friend to her brother.
While I still think fears of losing me, and 'it's wrong' cause her to hold back, she also, sometimes directly, sometimes more subtly, does make it clear she craves female companionship.
So I would still say 'practicing' poly right now, even if it's 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.