A sure way to rile up the voters is with an attack ad.

The supporters of the victimized candidate will be furious at the mudslinging. Neither side wins — or do they?

This Hawaii primary election season we have seen an explosion of misleading, nasty and uncalled-for negative ads.

There is something about Hawaii politics that forces candidates and their supporters to put a smiley face on local politics, ignoring the fact that Hawaii dives into negative ads just as much as politicians do in any other state.

“This is not the Hawaii way,” go the aphorisms, but Hawaii politics is no different than any other political atmosphere with candidates desperate to find the winning edge to separate their campaign from the others.

Political consultants are quick to explain the reason candidates or groups hoping to move a race use negative ads: It works.

Hawaii state Rep. Sylvia Luke this year has been the victim of some of the lowest attack ads of the campaign year, thanks to the Hawaii Carpenters union.

The Honolulu Star-Advertiser reported that Luke said she was the target of “a pretty aggressive smear campaign” by the political arm of the Hawaii Carpenters union because of her opposition to long-term state funding for the city’s troubled rail project.

For more than a decade, Luke has been a low-key but effective opponent to the rail project. The Carpenters, always hungry for more development-fueled construction jobs, have a history of savaging politicians fighting the controversial, long-stalled, over-budget rail project.

The union did the same thing when former Gov. Ben Cayetano ran for mayor of Honolulu and threatened to shut down the rail project. The union did not run commercials defending rail; it attacked Cayetano personally, much like how it worked over Luke this year.

The difference now is that politically powerful interest groups are out in the open: You can trace the money, although the Carpenters and their allies don’t leave a clear path.

Decades ago, Hawaii’s political powers were just as willing to play rough in local politics, but there was no score sheet to publicly keep track of wins and losses.

Message trees were set up, the coffee hours were not publicized and there were no internet-fueled alerts to run down or trash the political opponent of the month.

In 1986, Hawaii Congressman Cec Heftel resigned his federal post to run for Hawaii governor. While he was leading the polls for a while, his campaign was the victim of a series of word-of-mouth rumors and slurs that were cited as the major reason why he lost the Democratic primary.

Being a congressman is one thing; being on the inside in Hawaii’s tightly held Democratic establishment is another; and just holding office is still another. Heftel never enjoyed a close fit.

There is no law that allows every politician into the backroom where the deals are made, but it is obvious that Hawaii has its own set of “No Admittance” signs. This year’s winners will have to learn if they fit in.

Richard Borreca writes on politics on Sundays. Reach him at 808onpolitics@gmail.com.