'Born This Way' sold 900K (3xPlatinum) without a re-release. Check your receipts.
Katy had better singles sales, but all you need to do is look at their tour dates there to see who is bigger. It's not like everything revolves around chart receipts. Gaga also has a 9xPlatinum selling album.
Katy's re-release didn't bolster her album. It was at 1m before POM. Katy recently is bigger but Gaga was massive in a way Katy has never been. Overall it's gaga, her tour alone had 2m people wanting to buy tickets. That for the UK is ****ing huge. Believe me, we don't go that mad for tours.