A new 527 group, bornalivetruth.org, released an ad targeting Obama's opposition to a bill in Illinois known as the "Born Alive Infants Protection Act," which opponents said would weaken Roe v. Wade. On the same day, Moveon.org released an ad, "My Friends," attacking McCain's ties to lobbyists.

Anti-Obama Ad from Bornalivetruth.org:

Anti-McCain ad "My Friends:" from Moveon.org

UPDATE: On September 17, the group Vets for Freedom released an anti-Obama ad comparing remarks by General David Petraeus and Barack Obama on the surge:

UPDATE (9/19): The Obama campaign released a response to the "Born Alive" ad, refuting its claims and linking the 527 ad to the McCain campaign: