Is it possible to run a game where only the DM and one other player in online is online?

DMing from across the country and basic setup will be me running game over roll 20 and my friend logged in as player, he'll be streaming his screen to his TV and the rest of the player will be sitting around his coffee table. Is there a way to setup him to have control of the other players stuff from one account, or run more than one party member? Or will I basically be running both the PC and monsters on my end and having the party dictate their moves to me?

Yes, you just give his account in the game permissions to read & edit the journals and tokens of the other PCs. 

It's entirely possible. It's common enough that there's a wiki page for it.

I think you want Andrews solution. Go to each of the characters and set the controlled by/edit setting to your friends account name in addition to the intended player. He will then be able to treat all the characters as if they were his. You can also do this if a player is absent and you want someone else to "drive" their character. Watch out for the fight at his house when things don't go the way they want. Obviously any one at his house can move the mouse or use the keyboard. If you think you are going to be switching back to normal play you can also consider creating a new account and calling it "The Party" and giving it access to all the characters. Another post has reminded me that there is a limit on the number of compendium shares you can have. So extra accounts may not have access to these resources or the charactermancer. Be aware that dynamic lighting will not be as good as they will see everything that any one of them can see.

Mel C. said: I think you want Andrews solution. Go to each of the characters and set the controlled by/edit setting to your friends account name in addition to the intended player. He will then be able to treat all the characters as if they were his. You can also do this if a player is absent and you want someone else to "drive" their character. Watch out for the fight at his house when things don't go the way they want. Obviously any one at his house can move the mouse or use the keyboard. If you think you are going to be switching back to normal play you can also consider creating a new account and calling it "The Party" and giving it access to all the characters. Another post has reminded me that there is a limit on the number of compendium shares you can have. So extra accounts may not have access to these resources or the charactermancer. Be aware that dynamic lighting will not be as good as they will see everything that any one of them can see. I could have sworn there is an obscure page setting that sorta fixes shared vision issues but maybe it died when UDL came out.