Can my nerd attack fail?

Nine9Nines wrote:
Attacking:

Random town

Castle
Win: 140 Elixir, 50 Gold
Lose: 10 Elixir, 2 Gold

House
Win: 70 Elixir, 25 Gold
Lose: 5 Elixir, 2 Gold

Friend's town

Castle
Win: 25 Elixir, 10 Gold
Lose: 10 Elixir, 2 Gold

House
Win: 18 Elixir, 8 Gold
Lose: 5 Elixir, 1 Gold

Defending:

Castle or House
Won: 20 Elixir, 10 Gold
Lose: 10 Elxir, 5 Gold

-From simpsonswiki care of LPNITA

So yes, if your nerds aren't successful in destroying the buildings you set them to attack in random/neighbor towns, you do still get elixir/gold, but it is a smaller amount than if they are successful.

In fact, the majority of the nerds you send out to attack will likely fail (especially early on in the event). That's why the consensus seems to be that sending one nerd per building is the wise thing to do. That way you at least get some reward for each nerd. If you were to send multiple nerds to attack one building, and that building is successfully defended by the owner, you would still get the same payout as if you had sent only one nerd.