Complex sentence: She defeated two challengers in the August 14,2012, Democratic primary to become the Democratic nominee in Connecticut's 5th congressional district, and on November 6,2012, she defeated challenger Andrew Roraback to become the Representative-elect.
Split into simpler sentences: She defeated two challengers in the August 14,2012 Democratic primary to become the Democratic nominee in Connecticut's 5th congressional district. On November 6,2012 she defeated challenger Andrew Roraback to become the Representative-elect.