Simplify the following text for a Grade 10 native English-speaking person.
Original: Gerhard SchrÃ der led the coalition of SPD and Greens to an eleven seat victory over the Christian democrat challengers headed by Edmund Stoiber ( CSU ) .
Simplified: Gerhard SchrÃ der led the coalition of SPD and Greens to an 11 seat victory over the CDU\/CSU headed by Edmund Stoiber ( CSU ) .