Until recent weeks, one of the least understood aspects of the Democrats' primary contest was the role of superdelegates. These are Democratic Party insiders, members of Congress, and other officials who can cast ballots at the party's national convention this summer.

But now these unelected delegates are coming in for a close inspection, because neither Hillary Clinton nor Barack Obama can win their party's nomination without superdelegate support. The big Pennsylvania primary on April 22, for example, has only 158 delegates at stake (each of them will be pledged to support one of the candidates). By comparison, there are a total of 795 superdelegates, none of whom are required to honor the will of the voters of their state at the party's convention.

Sound undemocratic? It is. That the 2008 Democratic nominee for president will be chosen by individuals no one voted for in the primaries flew for too long under the commentariat's radar. This from the party that litigated to "make every vote count" in the 2000 Florida recount, reviled the institution of the Electoral College for letting the loser of the national popular election win the presidency, and has called the Bush administration illegitimate ever since.

Democratic Party reforms in 1982 gave super-delegates about 20% of convention votes -- so that party greybeards can stop a popular, but politically extreme, candidate from seizing the nomination. The Democrats deliberately rejiggered their party's rules to head off insurgent candidates, like a George McGovern or a Jimmy Carter, who might be crushed in the general election. Unelected delegates thus have more than twice the votes of the richest state prize, California.

So much for unfiltered democracy. In truth, the Democratic Party runs by rules that are the epitome of the smoke-filled room and ensure, in essence, that congressional incumbents exercise a veto power over the nomination.