This primary election had the highest number of registered voters in the state’s history, a big target for candidates who spent a total of $3.4 million on television ad buys since May.

Civil Beat rounded up the public files at first from the individual television stations — KHON, KGMB, KHNL, KFVE and KITV. Then, starting July 1, we’ve checked the files online on the Federal Communications Commission website to discern how much money candidates were spending on television ads.

The biggest spender, week after week, was U.S. Sen. Brian Schatz, who was locked in a tight Democratic primary race with U.S. Rep. Colleen Hanabusa. Schatz spent more than $1 million on ads, while Hanabusa spent less than half that — about $400,000.

Hawaii candidates spent over $3.4 million on television ads since May, approximately $618,500 of which was spent on ads airing the week leading up to the primary.

In the final week, Schatz spent more than $170,000 on television ads, including $3,000 apiece for spots on KHON’s 6 p.m. and 10 p.m. newscasts. League of Conservation Voters, a pro-environment group that supports political candidates that advocate for environmental conservation and preservation, spent approximately $340,000 on television ads from July 26 through the primary endorsing Schatz.

Hanabusa spent roughly $66,800 on final-week ads, including $1,300 apiece spots during KHON’s 6 and 10 p.m. newscasts and an $875 spot airing during KGMB’s sci-fi drama “Extant,” starring Halle Berry. A group entitled “Women Vote!” supports electing women into office, has spent nearly $200,000 from July 26 through the primary in television advertisements to advocate for Hanabusa.

Gov. Neil Abercrombie was the next biggest spender behind Schatz, buying close to a half-million dollars’ worth of TV spots in a losing bid for re-election. His Democratic primary opponent, state Sen. David Ige, didn’t start running TV ads until mid-July and spent a total of $73,750 on them. Ige did receive extra support from the Hawaii State Teachers Association which bought approximately $110,000 in television ad buys championing for the state Sen. from July 16 through the primary.

Republican gubernatorial candidate Duke Aiona spent just under $95,000 on TV ads that ran intermittently from May 26 to July 20.

In the race for the Democratic nomination for Congressional District 1, Donna Mercado Kim and State Rep. Mark Takai spent heavily on ad buys, while City Councilmen Ikaika Anderson, Stanley Chang and Will Espero spent much less.

Kim spent over $316,000 on ads that started in mid-May, while Takai spent $217,000 on ads that started July 10. Takai, the Army veteran who won the race, was also endorsed by Vote Vets with approximately $100,000 in television ad buys supporting the candidate.

Chang, who intermittently bought ads beginning in May, spent $125,000. Since mid-July, Anderson spent over $60,000 on TV ads. Espero bought his first ads at the end of July, and spent a total of $15,800.

Lt. Gov. Shan Tsutsui nearly doubled the TV ad spending of his Democratic primary opponent, state Sen. Clayton Hee. Tsutsui spent over $400,000 while Hee spent roughly $200,000 in a losing effort.

Television ad buys that aired during 2012 primary season totaled approximately $5.5 million, a roughly $2 million increase from this years expenditures. Greater spending in 2012 could be explained by high stakes races for U.S. Senate and Honolulu Mayor, not to mention the over $1 million spent by Pacific Resource Partnership in pro-rail advertisements.