Denied Childers a chance at winning a seat and thus endangered further the party's Senate majority.
You do realize Travis Childers was never going to win anyway?
Far better that they devote their energies to winnable races than go down this rabbit hole.
The odds were not impossible (especially if McDaniel pulled an Akin) and even if Childers had lost, a truly competitive race in Mississippi would have laid the foundations for future Democratic efforts. Indeed, it might force the GOP to devote additional resources to this state.
Force the GOP to spend money, yes. Lay the foundation for future Democratic efforts? Apart from a couple other candidates (Jim Hood, Ronnie Musgrove) you're not likely to get as good a Dem or as bad an R as Childers-McDaniel.
With Mississippi so racially polarized though and the state beginning to trend towards Democrats, a McDaniel win this year would have set Hood, Moran, Presley, or maybe a Dem State Rep./Sen. up to knock McDaniel out in 2020 when the environment is more friendly. I agree it really wouldn't be worth it spending loads of DSCC money for Childers for the simple reason that Childers outside help would be counterbalanced by McDaniel's help from the NRSC. Neither national party would really be enthusiastic about helping McDaniel and Childers anyways and efforts at winning this would be futile.
I do have to give an HP to the black Cochran voters though. What they really did doesn't exactly represent party unity. Even if most, if not all, of those blacks Democrats were eligible to vote in the Republican primary (meaning they didn't vote in the Dem primary), there's still the problem that they didn't want to help Childers out at all in his Tea Party challenge from Bill Marcy, yet they were more than willing to help someone who was ideological further from them in his Tea Party challenge. I understand MS's non-partisan and you can vote in any primary you want, but most of those blacks who voted Cochran vote Democrat elsewhere and this race should have been no exception to that. Ohio has closed primaries, but if we did have open primaries, I would never vote on another ballot of a party I don't ideologically belong to.
As an Ohioan, that's easy for you (or me) to say. We don't get screwed over if Cochran loses. I was initially in your camp on this before the primary, but between than and the run-off I realized it isn't really right to ask one state to get rid of the only thing it has going for it just to give us 33% chance of picking up a seat instead of having no chance.