Simplify the following text for a Grade 7 native English-speaking person.
Original: After serving as the mayor of Bucharest from June 2000 until December 2004 , he was elected President in the Romanian Presidential Elections of 2004 and inaugurated on December 20 , 2004 .
Simplified: He won the office in the 2004 presidential election . Prior to becoming President , he was the Mayor of Bucharest from June 2000 until December 2004 .