Who did Jesus die for? The sheep. The sheep come to Christ, period. Not a drop of His blood is shed in vain.
Your verse, if understood as a "bumper sticker" is universalism We don't want to go there, do we?
My verse? Gee, I didn't write it, I just quoted it.
So far you have not given a single verse that says that not one drop of Christ's blood was shed in vain.
It would appear that the "universal atonement" verses outnumber the "limited atonement" verses about 2 to 1, maybe even 3 to 1 . And so far you have no bumper sticker verses to back up your bumper sticker slogan. If you find one, let me know. John 10:15 just doesn't cut it. It does not necessarily mean what you (by your slogan) claim it means .