Minority groups often fight broadening the base of local government because they fear their power will be diluted. These are the three most popular voting systems to enhance minority representation:

CUMULATIVE VOTING

How it works: Each voter gets one vote for each seat to be filled on a council. A voter can use all votes for one candidate or spread them around.

Example: In a race to elect five candidates, a voter could put all five votes on a favorite. The five candidates with the most votes win.

The strategy: Minority groups and special interests can concentrate their votes.

Who uses it: Many corporations, to protect interests of minority shareholders, use cumulative voting to elect boards of directors. Cumulative voting was used to elect the Illinois state legislature from 1870 to 1980.

LIMITED VOTING

How it works: Each voter gets fewer votes than the number of seats to be filled on a council.

Example: In a race to elect five candidates, a voter can cast two votes. The five candidates with the most votes win.

The strategy: Members of a majority party or race can vote for only two candidates, limiting their ability to fill every seat.

Who uses it: Variations of limited voting are used to elect city councils in Philadelphia and Hartford, Conn. Limited voting has been used to resolve 30 voting rights cases in Alabama and North Carolina.

PREFERENCE VOTING

How it works: Each person gets a single vote in an election to fill a council, but voters rank candidates from first to last. Preference voting allows voters to support more than one candidate. If a candidate gets a majority of first preference votes, he or she wins. Then, the last place finisher is eliminated and the ballots are counted again. On ballots that listed that candidate first, the second choices are counted, possibly giving another candidate enough votes to win. The process repeats, with third, fourth and fifth choices, etc., until all seats are filled.

Example: In a nine-seat race, five candidates get enough votes to win in the first round. A voter's top candidate for an office does not get enough votes, but switching the vote to the second-choice gives the second-choice candidate enough votes to win.

The strategy: Most voters ultimately help choose a winning candidate, meaning that minority voters increase their chances of representation.

Who uses it:. Ireland uses preference voting to elect its parliament and New York City uses it to elect school boards.