"Experience keeps a dear school," wrote Benjamin Franklin, "but fools will learn in no other." Right now, Americans are getting a crash course in the folly of our general approach to filling vacancies in the United States Senate. But so far, there is little evidence that we are learning the obvious lesson.

This week, President Obama appointed Sen. Judd Gregg, a Republican, to head the Commerce Department. When the idea was floated, cynics suspected a sinister motive. New Hampshire has a Democratic governor, John Lynch, and the iron tradition is that a governor, faced with a vacancy, fills it with someone from his own party -- even if it differs from that of the departing senator.

As it happens, Democrats were already on the verge of gaining their 59th seat, assuming Al Franken's apparent victory in Minnesota stands. Gregg's resignation would give them the chance to reach 60, the magic number for the dominant party to do anything it wants.

But that suspicion was in error. Gregg told the president he would accept only if Lynch would name a Republican replacement, denying Democrats a filibuster-proof majority. Lynch agreed, choosing Bonnie Newman, whose promise not to run in 2010 gives both parties a fair shot at capturing the seat.

On the surface, this sounds good. Obama gets to reaffirm his commitment to transcending old enmities, improving the chances for bipartisan cooperation. The Cabinet gets someone who will discourage the president from veering too far left. The Senate balance remains intact, impeding Democrats from oppressing the minority.

It's a far cry from the debacle in Illinois, where a governor allegedly tried to sell Obama's vacant Senate seat for personal gain -- and who, when that reported attempt came to light, appointed Roland Burris mainly because he had the same skin color as Obama. By comparison, the New Hampshire approach looks like a model of responsible stewardship.

Until, that is, you remember the clear loser in the deal: the people of the state, who for the next two years will be represented by someone they have never elected to any office, didn't elect to this one and may not want. As a bonus for their trouble, if it turns out they do like her, they can't keep her.

Rod Blagojevich treated a Senate appointment as a get-rich-quick scheme. Obama, Gregg and Lynch treat it as a tool for arranging the Washington political landscape to their liking. In each case, the voters are reduced to potted plants.

These are not the only examples of politicians bypassing democracy. In New York, Gov. David Paterson toyed with naming Caroline Kennedy to replace Hillary Clinton, until she backed out and he chose Kirsten Gillibrand. In Colorado, Gov. Bill Ritter selected Michael Bennet to take over for Ken Salazar.

Delaware Gov. Ruth Ann Minner asked Ted Kaufman, a longtime aide to Joe Biden, to serve out his term. So right now, 5 percent of the nation's highest legislative body will consist of members installed without the consent of the governed.

Only a handful of states make a practice of holding a special election to fill vacant Senate seats. Most leave it to the governor if the opening occurs less than two years before the next regular election.

That may have made sense back in the days when senators were chosen by state legislatures, as stipulated in the U.S. Constitution. Voters didn't get a say until the 17th Amendment was ratified in 1913. But if democracy is a better way to choose senators for six-year terms, it stands to reason that it's also a better way to choose senators for two-year terms.

True, elections cost money. Too bad. If cost were the dominant consideration, we wouldn't have them at all. No one would argue that in a period of fiscal distress -- say, a recession -- we should suspend normal democratic procedures to conserve cash. So how can we justify dispensing with the voters when it comes time to fill a Senate seat?

Some governors are honest and conscientious in making such appointments. Some are not. But in the most fundamental sense, it doesn't matter. Even the most honest, public-spirited governor is incapable of divining whom the people would elect if given the chance. A single person should not be entrusted with such unchecked authority.

Rod Blagojevich proved that. And no other governor has furnished a convincing rebuttal.