I think it won't be higher than 15-20 on iTunes. It's really not the kind of song you're going to play again and again and especially during the summer. Nobody knew Christina was releasing her single today and I doubt those who hear will fall in love with the song. It's nothing special, the lyrics are really basic, not different from anything else and not really great for a ballad.
I think the only way we can hear about it is because the money will be given for a good cause.
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