Ari Fleischer
Ari Fleischer (born October 13, 1960) was the press secretary for U.S. President George W. Bush from January, 2001 to July, 2003. On May 19, 2003, he announced that he would resign during the summer, citing a desire to spend more time with his wife and to work in the private sector. He was replaced by deputy press secretary Scott McClellan on July 15, 2003.
Note: At the time this scene is set (April 2004), Ari Fleischer had already resigned as Presidential Press Secretary, "citing a desire to spend more time with his wife and to work in the private sector." Fleischer was replaced by his deputy, Scott McClellan, on July 15, 2003.
For dramatic and production purposes (i.e., not introducing a new character with only one line in the last minutes of the movie) the actor who played "Ari Fleischer" in the earlier (and important) "White House Lawn" scene was used here instead of a "Scott McClellan" character suddenly appearing.