If he keeps up the fight, he is likely to lose, unnecessarily deprive Minnesota of a second senator, end his political career seen as a sore loser, and hurt his party in a state that is eager for this fight to be over. His team has talked enough about further legal challenges that if he leaves now, he will get some points for grace. (Needless to say, that sentiment would not be universal.) But this is, I think, the last moment where he can exit with some dignity.
P.S. I got this response to my post from yesterday urging Coleman to give up: “You Repuglicans are like rats leaving the sinking ship. You’re only telling Coleman to stop because it’s clear he’s lost. Classy.”
Leaving a sinking ship is actually not proof of rathood. Non-rats do it too. That’s why sinking ships often have survivors. I generally think that futile endeavors should be abandoned, but only once their futility is clear. If that’s the charge, I’m guilty.