I would say "wish you were here" and "let me go" by avril

Marry The Night.

This song didn't flop, but it deserved to be huge.

All of the Avril songs that flopped which is Rock N Roll, Smile, Wish You Were Here, Let Me Go and The Best Damn Thing.

Ready Or Not and Hurricane by Bridgit Mendler deserved to be more sucessful in the US but her new single is coming soon so whatever.

"Free" by Haley Reinhart, "Oath" & "With Ur Love" by Cher Lloyd

C'Mon
Crazy Kids

Thinking of You
Nothing in This World (by Paris Hilton)

END OF TIME
And I'm still PRESSED About the treatment it got

Marry the Night - Gaga
Rock N Roll - Avril
C'Mon - Ke$ha

Ke$ha - C'Mon
Ke$ha - Crazy Kids (without will.i.am)
Avril Lavigne - Rock N Roll

DWUW & Marry The Night

And it all comes down to how messy Gagas last two eras have been.

If U Seek Amy, Radar, Work Bitch, Slave 4 U, Lucky, Stronger, Overprotected, Boys, Everytime, Do Somethin', Piece of Me, Break the Ice, I Wanna Go, Perfume...

What Now

Marry The Night - Lady Gaga
People Like Us - Kelly Clarkson
Let Me Go - Avril Lavigne (even though I don't normally use ha)
WHAT NOW - RIHANNA, still pressed this flopped

Waking Up In Vegas

Do What U Want and Countdown.

Radar

C'Mon