There is no mention of "not one drop of Christ's blood being spilled in vain."
Honestly, bumper sticker slogans like "And, not a drop of Christ's blood is spilled in vain." really should have bumper sticker verses to back them up.
Like this one:
And he is the propitiation for our sins: and not for ours only, but also for the sins of the whole world. (1 John 2:2 KJV)
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?