This is another tough one. The Eladrin are the first elvish race I am actually inclined to play. True 'High Elves' ala Tolkien. But Half-Orc have a spot in my heart too.
This is even harder than the Dwarf vs Changeling poll!!
Half-Orcs sucked in too many editions prior to 4e. I didn't like their implied origin in previous editions, and their implied angst did nothing for me either.
I'd guess compared to all of the races at once, as in the seeding, the presence of all the other elves, especially Elves, who rightfully took the name right out from the High Elves, adversely affected their votes. On an individual matchup basis, however, most of the people who like Elves also tend to like Eladrin, or at least more than they do many of the other races. I like them more than half-orcs, but if they were up against Gnome, Changeling, "real Elf," and possibly some of the other survivors, I'd have voted for their opponent. Well, no actually. I don't like Dwarf, Human, and Halfling. All the other races I liked more than Eladrin were voted off already.