The McCain campaign does not require passport numbers for online donations but spokesperson Tucker Bounds said, "We have been very diligent about the integrity of our donations."
Neither campaign has made a huge effort to fundraise abroad. McCain has had three fundraisers in London, one he personally attended, one his wife, Cindy, personally attended and a third that John McCain attended on a teleconference, according to the campaign.
Barack Obama has not attended any fundraisers abroad, although his wife, Michelle, spent a day in London fundraising. The Obama campaign has sent other surrogates to fundraisers abroad, including Democratic National Committee Chair Howard Dean in London, New Mexico Gov. Bill Richardson in Madrid, and former Secretary of the Navy Richard Danzig in Paris, according to the campaign.