What happens if you hold an election and nobody wins? That's what the British were trying to figure out.

A member of the outgoing Labor Cabinet told the BBC, "We lost the election, but the Conservatives didn't win it." What kind of message is that? Maybe one that needs to be heard on both sides of the Atlantic.

Prime Minister Gordon Brown's Labor Party suffered its worst losses in 80 years. In the end, however, Brown "snatched defeat from the jaws of disaster," as one wag put it. David Cameron's Conservatives enjoyed huge gains, yet still ended up shy of a majority.

Two-party politics is not working on either side of the Atlantic.

The Liberal Democrats, Britain's perpetual third party, were expected to make a breakthrough in this election under their popular young leader, Nick Clegg. Instead, the Lib Dems ended up losing seats. But now Brown has resigned as prime minister. Cameron is taking his place and forming a coalition government with the Liberal Democrats.

What were Britain's voters saying? Probably this: We want change but not pain. That's a mandate for moderation. Although vast numbers of voters were disillusioned with Labor, they were also deeply distrustful of the Conservatives. Cameron tried to put a new, more modern and compassionate face on his party. But he is still a rich, privileged young man from the relatively prosperous south. His message of austerity did not sell well in Britain's bleak industrial north.

Despite Clegg's poor showing, he ended up holding the balance of power after the election. And he's using his role as kingmaker to bribe the new government to deliver on the Liberal Democrats' top priority, election reform.

Specifically, they want proportional representation, which would end the two-party domination of British politics. Where's the fairness in a system in which the Liberal Democrats win 23 percent of the vote but only 8 percent of the seats? The outcome "made it absolutely clear that our electoral system is broken," Clegg said. A You Gov poll taken just after the election showed that by nearly 5-to-1, British voters favor a more proportional system of representation.

Cameron acknowledged that his country voted for "a new approach to politics," meaning a more centrist and collaborative style of government. That's what two-party systems are supposed to deliver. To win a majority, the parties are expected to compete for votes in the center.

But that's not happening in Britain or the United States. Instead, the parties have come to be dominated by their extremes. Because politics is intensely polarized, voters are losing faith in the rotation of power as a way to ensure moderate government. A presumed virtue of the two-party system is that it produces conclusive outcomes by giving the winner an exaggerated majority. But it's not even doing that. Two-party politics failed to deliver a decisive result in the United States in 2000 or in Britain this year.

Under proportional representation, no party would be likely to win a majority. The spectacle of unseemly wheeling and dealing would follow every election. Cameron has warned that "party managers would choose a government on the basis of secret backroom deals." Look at Israel. That country has the most proportional system on Earth. It took Prime Minister Benjamin Netanyahu three months of hard bargaining to construct his shaky majority.

All of this sounds ominous until you realize that shameless political bribery is exactly what Britain witnessed immediately after the election. It's precisely the way the U.S. Congress routinely passes legislation. Remember the "Cornhusker Kickback" and the "Louisiana Purchase" that helped get health care reform through the Senate?

Two-party politics is not working on either side of the Atlantic. It's not producing what voters want: moderation and balance. Instead, it's producing politics that lurches from left to right. Proportional representation would give Britain no-majority government (and the Liberal Democrats would be kingmakers forever, which is why they like it). Would that be any better? Maybe.

The major parties are no longer what they once were, broad-based coalitions. They're more like tribes, with exclusive faiths and fetishes. So the only way to get a broad consensus in government might be to force the tribes to work together.

This article appeared in the Saturday, May 15, 2010 edition of National Journal.

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