They are all singing altogether. It's the Group-Performance (At the end of each Episode), and these performances usually sell the most (Don't Stop Believen', Like A Prayer, Total Eclipse of the Heart...)
I hope Lea has her own solo part in this version. I can already hear her singing "Wants your Bad Romance" in a belted note (The same way she did in Take A Bow)
Oh well, I know she'll rock Poker Face anyway!
For those who are saying Glee ruined the song or whatever, Why are you here? Why did you even bothered listen? Nobody forced you. This is a theatrical version of the Song, and I bet after all of you will see the effect it does on the original songs on iTunes (Poker Face and Bad Romance) you'll eat your words up and start praising Glee.
TEOTH is sung only by Rachel, *****, Finn and Jesse.
I LOVE THIS GIF SO MUCH!!!!
I LOVE glee, and I do like the preview, BUT It's like something is missing there.. Not sure what thogh..I REALLY hope lea has a solo in Bad Romance but anyway I can't wait to Poker Face..
Lea + Idina + Poker Face (slow) = EPIC!
is annoying 
. I'm sorry, but plzz change your avatar 
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