Possibility:
Ariana Grande f/ Iggy Azalea - "Problem"
A Great Big World f/ Christina Aguilera - "Say Something"
Iggy Azalea f/ Charli XCX - "Fancy"
Katy Perry f/ Juicy J - "Dark Horse"
Shakira f/ Rihanna - "Can't Remember to Forget You"
Although my choice would be:
A Great Big World f/ Christina Aguilera - "Say Something"
Iggy Azalea f/ Charli XCX - "Fancy"
Mike Will Made-It f/ Miley Cyrus - "23"
Pitbull f/ Ke$ha - "Timber"
Katy Perry f/ Juicy J - "Dark Horse"
With Mike Will winning