I think she won't be #1. But the following weeks it would be possible. I'm more excited about the week she debuts it in the VMAs. She'd have even higher airplay by then. Or the weeks following her debut of the music video.
I'm very impressed tbh, I never did doubt Katy but I didn't think she'd be able to hold #1 for this long, especially with such a huge lead I reckon she'll be able to push 500k.
it's not totally out of the question
if her airplay continues to build up nicely then more people could potentially buy the single during the weekend
I say 450K is a generous estimation (hope no one's bookmarking me )
as in I expect her to sell 500K
GET HA 
I reckon she'll be able to push 500k.
the bad news for some stanbases 
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