Incumbents everywhere are understandably wary of making alterations to the political system that brought them to power. That's why public financing of campaigns, invariably raised as a solution in any state suffering through an embarrassing scandal, rarely seems to get very far. Yet public financing experiments known as "clean campaign" laws are finally starting to gain traction around the country. So far both voters and candidates seem pretty happy with them.

Maine and Arizona have been offering public funds for most state campaigns since 2000. Connecticut is about to join them. It will offer public financing for all state offices starting next year. Under each of these laws, candidates have to raise a threshold amount in smaller private donations to demonstrate credibility.

It was widely predicted in both Maine and Arizona that candidates would spurn the voluntary public funds, but that hasn't happened. In Maine, 84 percent of the legislators chosen in 2006 used public money, while in Arizona nine out of the 11 current statewide officeholders, including Governor Janet Napolitano, financed their most recent campaigns with "clean" money.

But is public money really any cleaner? You can't say public financing has prevented interested parties from making their financial presence felt. Clean campaign laws do nothing to prevent outside groups from spending huge amounts independently in important contests. Nor have the laws slowed the growth of fundraising by political action committees operated out of legislative leadership offices.

And there are other obstacles. Campaigns in Maine are exceptionally inexpensive to run: In some districts, $5,000 is enough to pay for a decent House effort. That has its good points--supporters of the law love to talk about the single-mom waitress who took advantage of public money to become a legislator--but others complain that the combination of cheap campaigns and easy money has brought a raft of dubious place-seekers out for a free ride.

Still, the recent round of laws has some advantages over public financing schemes of the past. For one thing, the amounts available are adjusted as spending increases each cycle, so the public grant doesn't gradually become inadequate to finance a campaign, as happened in Wisconsin in the 1990s. In addition, the new laws contain triggers that provide extra help to candidates whose opponents spend private funds like mad. Clean campaign laws don't abolish the influence of money in politics--nothing could--but they do seem to separate many lawmakers from the rigors and ethical challenges associated with fundraising. Overall, that's a good thing.