Complex sentence: The matter was decided in the election, where the smaller city of San Bernardino barely won the contest by only two votes when some of the ballots from a precinct in Belleville were said to have been burned by "accident".
Split into simpler sentences: The matter was decided in the election, in which the smaller city of San Bernardino won the contest by only two votes. Some of the ballots from a precinct in Belleville were said to have been burned by "accident".