Simplify the following text for a Grade 8 native English-speaking person.
Original: Dulles served from July 7 , 1949 , to November 8 , 1949 , when a successor , Herbert Lehman , was elected , having beaten Dulles in a special election to fill the senate vacancy .
Simplified: Dulles was part of the Senate until 8 November 1949 , when an election for the position was held and he lost .