And here is a very insightful pro-PR article by Michael Lind, in The Atlantic Monthly, August 1992.
Electoral systems can be divided into two fundamental varieties: the plurality, or "winner-take-all," method and the party-list method, with proportional representation (PR). Under the plurality system a representative is elected by a simple plurality (or in some cases a majority) of voters in a single-member district. In contrast, in PR systems the country is divided into multimember districts (in a small country such as Israel, the entire nation may be a single district). Several parties present lists of candidates within each multimember district; the electorate casts its votes for the parties, rather than the candidates; and then the seats are allocated among the parties, on the basis of the proportion they received of the total vote.
The United States has inherited the plurality method from Britain, which maintains it as well (Australia has broken with the British tradition in favor of more-modern methods). The Anglo-American method makes possible distortions of the democratic process which are simply impossible under PR. Imagine a country with a plurality system in which there are two major parties, X and Y. Those who vote for party X, even if they make up no more than 51 percent of the voters in each single-member district, may elect 100 percent of the representatives; those voting for party Y, although they constitute 49 percent of the population, MAY END UP WITH NO REPRESENTATIVES AT ALL. Now suppose that X and Y are joined by a third party, Z. If in every district X receives 40 percent of the vote, Y 38 percent, and Z 22 percent, X will control every seat in the legislature, even though 60 percent of the population voted for other parties.
These examples may seem extreme, but there are cases in which plurality systems have elected one party even though another received a greater number of votes. For example, in 1974 the British Conservative Party lost its majority of seats in the House of Commons, even though it received 300,000 more votes than the Labour Parry. In the latest British election John Major's Conservative Party retained a majority in the House of Commons, even though a majority of British voters cast votes for parties other than the Conservatives.
Similar distortions exist in the United States. In 1990 the Republican Party won 45 percent of the popular vote but was reduced to 38 percent of the seats in the House. The Democrats, with 53 percent of the popular vote, received 61 percent of the seats. As in Britain, a strong third-party challenge could permit a minority of American voters to elect a majority of members of Congress. Nothing remotely comparable to these distortions is possible under proportional representation.
Another advantage of PR is the way it makes gerrymandering difficult or impossible. In multimember districts every party or voting bloc will be represented more or less in proportion to its strength in the entire electorate, regardless of how the district lines are drawn. It is only in plurality systems, in which an area of several blocks may make the difference between losing everything and winning everything by a few percentage points, that there is a strong incentive to gerrymander.
Along with partisan gerrymandering, today's government-mandated racial gerrymandering could be eliminated by PR without curtailing the voting power of ethnic minorities. Federal courts have gone from striking down a "strangely irregular twenty-eight-sided" district drawn to prevent black voters from pooling their strength to requiring the creation of equally strange districts to encourage the election of black candidates. Under PR, blacks and Hispanics would find it much easier to elect candidates of their own ethnic group--if they chose. But they would not be maneuvered into such a choice by being electorally ghettoized in safe "minority" districts. Other ethnic minorities, who do not receive preferential gerrymandering, would benefit as well. For example, the federal courts have recognized the right of blacks to have districts redesigned to their benefit--but not the right of Hasidim. PR would eliminate the need for heavy-handed efforts that force some electoral minorities to waste their votes while artificially magnifying the weight of other minority votes. At the same time, PR would increase the power of all minorities--ethnic, religious, ideological, economic, blacks and Hasidim--to elect representatives to Congress, on whatever grounds they chose.
Proportional representation has an additional advantage, insofar as it permits the election of talented or distinguished persons who can get a minority of the vote in a district but who disdain to indulge in the vulgar exaggeration and false promises necessary to win a majority. Noting that "the highly cultivated members of the community" find it difficult to be elected under a winner-take-all system, John Stuart Mill wrote,
"Had a plan like Mr. Hare's [for proportional representation] by good fortune suggested itself to the enlightened and patriotic founders of the American Republic, the Federal and State Assemblies would have contained many of these distinguished men, and democracy would have been spared its greatest reproach and one of its most formidable evils."
