Russian nickname for Theodore?

[american_mama]

Really quick.. does anyone know the spelling of the Russian nickname Fedya/Feja? It's a common nickname for Theodore, I believe. I would really like to print some nametags for a party tonight and cannot ask the person at this hour. I just need to know the correct spelling, since I know the name is Fedja/Fedya/Feja.

[vonfirmath]

I see Fedor and Fyodor

(This is my son's name, but I had not known this association before. Thanks!)

[kozachka]

Fedor. That's how one of my former bosses spelled his first name. Did not realize it was Theodore in English.