LOS ANGELES (AFP) -- White House hopeful Barack Obama won the Democratic caucuses in Hawaii, inflicting a further defeat on rival Hillary Clinton, U.S. media reported on Wednesday.

Obama has gained more ground over his rival, Clinton, in the contest to win the Democratic nomination to run for U.S. president.
Obama, the senator for Illinois, has won the primary in Wisconsin.
This puts huge pressure on Clinton to win in Ohio and Texas next month.
John McCain won Wisconsin for the Republicans, boosting his front-runner status in his party's contest.
With 99% of precincts having reported in Wisconsin, Obama had 58% of the vote to Clinton's 41%.
The state has 74 Democratic delegates at stake. The Associated Press (AP) news agency said Obama was projected to win at least 38 of them, and Clinton 27, with nine still to be awarded.
Seeking momentum
The BBC's Jonathan Beale says Wisconsin was a significant victory for Obama, eating into Clinton's support base.
It is a major disappointment for Clinton, the senator for New York, who had been hoping to restore momentum to her campaign.
Instead, Obama was reported to have gained almost equal support from white women, and to have polled well from working-class Democrats - both groups which have usually supported Clinton.
He also took the youth vote and six out of 10 self-described independent voters, according to exit polls for ABC.
But he and Clinton are already looking ahead to March's bigger contests in Ohio and Texas, seen by analysts as crucial to her credibility as a candidate.
Speaking at a victory rally in Houston, Texas, Obama said: ""The change we seek is still months and miles away and we need to get all of Texas to help us get there.""
Addressing a rally in Youngstown, Ohio, Clinton said the primary campaign was ""about picking a president who relies not just on words but on work - hard work to get America back to work"".
Before the results from Wisconsin were calculated, Obama held a slight lead over Clinton, with 1,280 delegates to her 1,218.
It will take 2,025 delegates to secure the Democratic nomination at the party's national convention this summer.
McCain, the senator for Arizona, now has almost four times as many delegates as his main rival, Mike Huckabee.
With 99% of precincts reporting in Wisconsin, he led with 55% of the vote compared with 37% for Huckabee and 5% for Texas Congressman Ron Paul. There are 40 Republican delegates at stake.
The polls for AP suggested McCain had made headway with some core Republican voters, beating Huckabee overwhelmingly for the support of moderate Republicans.
The Washington Republican primary is the second vote in a two-part nominating contest - half its delegates were decided earlier in a caucus on 9 February, which was narrowly won by McCain.