Uhh . . . maybe don't record on a kareoke machine?
I know, just sing REALLY LOUD onto a new track and nobody will hear the echo on the first one.
No wait I know: junk it and start over. Yeah that's it!
If you still have THE EXACT SETTINGS of your delay and you did not use any feedback (what I do very often), then you might have another solution to work for you.
use your track and send it through the identical delay.
record the delay output only
invert the phase
add to original track until echo vanishes the best
gate in addition to remove the tails
In theory, this should work, but I'ver never tried