From the AP:
'The Secret Service has asked for an extra $9.5 million to cover unexpected costs of protecting the presidential candidates during what has turned into an historic year for the agency's campaign security job. Among other things, the extra money would be used for the added costs for the candidates' international travel and a late-in-the-game decision by Barack Obama to accept the Democratic nomination at Denver's Invesco Field at Mile High - an open-air, 76,000-seat stadium - instead of the 20,000-seat Pepsi Center ... 'Obama received Secret Service protection on May 3, 2007 - the earliest the agency has ever stepped in to protect a candidate. ... McCain picked up protection on April 27 of this year. During the 2008 campaign, the agency has protected candidates on about 1,500 trips; and each trip has included three to eight stops. To secure the candidates on these trips, the Secret Service has used about 2,200 magnetometers to screen about 1.5 million people.'