By Michael Beckel Center for Responsive Politics May 13, 2010

Votes are already being cast in the free-for-all special election in Hawaii's 1st Congressional District, and a Republican candidate has emerged with the most cash on hand in the campaign's final stretch.

The election is almost entirely vote-by-mail, and ballots were mailed out to voters earlier this month. The district went for 2004 Democratic presidential candidate John Kerry by 6 percentage points, and Barack Obama carried the district by a whopping 42 percentage points in 2008.

Yet Republican Charles Djou, pictured above, a city council member in Honolulu, has nearly $170,000 more in the bank than the most well-financed Democratic candidate, and polls indicate Djou could pull out a victory in the strongly Democratic district.

Part of the reason why? The special election is playing out under rather special circumstances.

Fourteen candidates appear on the ballot to fill the House seat vacated by Rep. Neil Abercrombie (D-Hawaii), who resigned from Congress in February to focus on a gubernatorial bid.

These candidates are a mix of Democrats, Republicans and independents, and the winner only needs to garner a plurality of the vote.

There is no run-off mechanism, even if a single candidate fails to receive more than 50 percent when the votes are counted on May 22.

While most Republicans seem to have unified around Djou, two top-tier Democratic candidates -- state senate president Colleen Hanabusa and former Rep. Ed Case -- each argue that they are the stronger Democrat.

Neither has opted to drop out of the race to make way for the other.

Hanabusa is supported by labor, the Hawaii Democratic Party and the state's two Democratic U.S. Senators, Daniel Akaka and Daniel Inouye. Inouye's leadership PAC even contributed $10,000 to help her cause.

Many local Democrats in Hawaii, meanwhile, have scorned Case for his 2006 challenge to Akaka, yet he has been helped by the Democratic establishment in Washington.

While the Democratic Congressional Campaign Committee never officially endorsed Case, it was widely reported that the group favored him over Hanabusa.

The DCCC spent $314,000 on advertisements blasting Djou but recently dropped its financial support because "local Democrats were unable to work out their differences" and Case and Hanabusa were "splitting the vote."

Among the Democrats in the race, Hanabusa has personally raised the most money -- raising more than $1.08 million, of which she currently has about $195,000 on hand.

Researchers at the Center for Responsive Politics are still processing and coding the most recent campaign finance reports, but through the first quarter of 2010, labor unions had contributed $57,000 to Hanabusa's campaign. Real estate interests had also contributed about $57,000.

Lawyers and law firms gave $47,000 to her campaign, and women's groups, led by EMILY's List, gave about $35,000.

Case's top financial supporters, meanwhile, have been individuals who list their occupation as retired. Such contributions account for more than $60,000.

Lawyers and law firms also gave big to Case, coming in at more than $44,000 in contributions. The agribusiness sector donated more than $13,000 to Case, while political action committees associated with or individual employees of labor unions have contributed just $250.

Overall, Case has raised about $821,000 and has about $154,000 left in the bank.

For his part, Djou has raised nearly as much as Hanabusa, but has spent far less. He has raised $1.07 million and currently has about $363,000 left in his war chest.

Like Case, retired people are his largest supporters, giving about $54,000.

The financial sector has given more than $32,000 to him, while the ideological groups and other politicians have given him $30,000 and health sector interests have given him about $29,000.

Republican groups and politicians who have given Djou direct financial assistance include the National Republican Congressional Committee ($5,000), the leadership PAC of House Minority Whip Eric Cantor ($5,000), the leadership PAC of retired Louisiana Rep. Jim McCrery ($2,500),  the leadership PAC of California Rep. Devin Nunes ($2,000), the leadership PAC of Oklahoma Rep. Tom Cole ($2,000), the leadership PAC of Michigan Rep. Dave Camp ($2,000) and the Republican Majority for Choice PAC ($2,000), which backs Republicans supportive of abortion rights.

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Center for Responsive Politics researcher Erin Williams contributed to this report.