Hawaii. The home of picturesque beaches, epic surf and honeymooners is also the scene of a one-of-a-kind Democratic Senate primary that owes its existence to a governor's refusal to grant a dying senator's wish.

Rep. Colleen Hanabusa (D-Hawaii) (Marco Garcia/AP) Rep. Colleen Hanabusa (D-Hawaii) (Marco Garcia/AP)

In the latest and most intense chapter of a years-long divide in the state Democratic Party along generational, political and ethnic lines, Sen. Brian Schatz (D) is trying to fight a spirited challenge from Rep. Colleen Hanabusa (D). A new poll released Tuesday confirmed what many have long believed: The race is shaping up as a dead heat.

Half the Republican senators running for reelection have drawn primary challengers this year. But Schatz is the only Democratic senator facing a serious primary threat. Riding on the outcome of his race: The future of the state's Democratic establishment, which is torn between competing factions.

Schatz is a close ally of of Gov. Neil Abercrombie (D) and a representative of a younger, whiter, liberal wing of the state Democratic Party. Hanabusa was very tight with the late-Sen. Daniel Inouye (D), dean of the old guard, whose 2012 deathbed wish was that Abercrombie appoint Hanabusa to replace him.

After more than a year under his belt in the Senate, Schatz is trying to show voters he is just what the state needs: a young up-and-comer with a liberal record who has quickly become close with Democratic leaders. He's been flexing his support from the likes of Senate Majority Whip Dick Durbin (D-Ill.), telegraphing to voters that he is capable of cultivating relationships in Washington that will pay dividends back home, where there has long been a tradition of legislators with a knack for steering federal dollars toward the islands.

Hanabusa, meanwhile, is underscoring her local ties. Among her backers: Inouye's widow; former governors George Ariyoshi and Ben Cayetano; and former senator Daniel Akaka, who served alongside Inouye.

"The one thing people really emphasize here in Hawaii is you've got to earn it," Hanabusa said in an interview Tuesday, adding, "you also don't disrespect your Kupuna, your seniors."

Age is one of the many sensitive topics associated with this race. Abercrombie recently told The Post's Philip Rucker that he thought Hanabusa, 62, was too old to build seniority in the Senate. Schatz is 41.

Another is the ethnic divide between Hawaii Democrats. Hanabusa, like Inouye, is an American of Japanese ancestry. Schatz and Abercrombie are white.

But the most sensitive topic in the contest is Inouye's dying request. Abercrombie's selection of Schatz, then his lieutenant governor, was seen by the late senator's loyalists as an insult to the man long-regarded as political royalty -- an insult worthy of a primary challenge. Abercrombie picked Schatz from a short list provided by the state Democratic Party that included Hanabusa and one other candidate.

One observer of state politics said Inouye's wish will help Hanabusa fire up her base, but probably won't win over undecided voters. "It's a way to mobilize people. It's a way for her to fundraise," said University of Hawaii political scientist Colin Moore. "I don't think people who are on the fence are going to see this as the thing that tips them over the edge."

When it comes to money, Schatz has the upper hand. Backed by Democratic leaders, the state's largest labor union and leading environmental organizations and activists, Schatz has outraised Hanabusa roughly 2-1 throughout the course of the election cycle. Hanabusa has been burning through cash at a faster pace, too.

"We are pleased to be leading by four points in The Mellman Group’s most recent poll of the race," said Schatz spokesman Clay Schroers, referring to a survey conducted for the Schatz campaign last month.

Schatz will need the money to help raise his name recognition. Another challenge: The lingering unpopularity of his biggest supporter, Abercrombie, who faces a primary challenge of his own from state Sen. David Ige (D). Polls show Abercrombie could be vulnerable. (Polling in Hawaii, it should be noted, is especially difficult, leading to sometimes conflicting findings. For example, another recent poll showed Hanabusa with an eight-point lead over Schatz.)

Clashes with the state teachers union and his initial support for a state entity to develop public lands (he later repealed it) have appeared to contribute to the governor's image woes.

"I think those two things gave people the impression that there was some mismanagement," said Moore.

The primary is August 9. Hanabusa said she expects things to ramp up in July when absentee ballots go out. Until then, in a state where retail politics matters a lot, expect to see both candidates logging as much face time as possible with voters back home, nearly 5,000 miles away from their days jobs in Washington.

"They want to touch you. They want you to know about you," said Hanabusa.

Hawaii congresswoman Colleen Hanabusa explains her home state's obsession with SPAM in Hawaiian cuisine. Also: Unheard stories about the late Sen. Daniel Inouye. (Jeff Simon/The Washington Post)