There's good news and not-so-good news for the our biennial exercise in democracy.

The good news: The number of people registered to vote in the Sept. 20 primary election has increased since 2006. The not-so-good news: The increase is less than 2 percent statewide.

It will be especially discouraging if the actual voter turnout followed a similarly weak trend. There are mayoral contests on three islands — including O'ahu. There are also a number of important legislative and council races to be decided in the primary.

The latest figures show that 667,647 Hawai'i residents are registered, roughly 67 percent of the 18-and-older population.

If past trends continue, far fewer will vote. In the past four primary elections, the average turnout was about 41 percent of those registered.

In a society that depends on civic engagement to thrive, the trend is disturbing.

It was not always this way. In the 1960s and '70s, voter turnout in the primaries went as high as 84 percent of those registered. In the general election, even higher: 93 percent.

Every effort should be made to encourage voters to show up at the polls on election day. Efforts should include: more aggressive get-out-the-vote drives from the political parties and independent groups; reforming election laws, including public financing and increased pay, to attract more and better candidates (31 seats are unopposed this year); and working to make the registration process simpler and more accessible, perhaps through an online system.

And voters should take it upon themselves to exercise their civic duty wisely. Today's Advertiser contains a complete guide to the primary election, including candidate profiles and detailed instructions on using the new ballots.

It's also not too late to register for the general election (see box).

In 2004, the last presidential election year, turnout was 67 percent of registered voters.

This year, with America facing a truly historic choice between Obama/Biden and McCain/Palin, it's hoped that the turnout will be large enough to make history too.