KEY POINTS:
MILWAUKEE - Senator Barack Obama won the Wisconsin vote to pick a US Democratic presidential candidate on Tuesday, handing rival Hillary Clinton a ninth straight defeat and leaving her White House ambitions hanging on the upcoming contests in Texas and Ohio, media projected.
Obama's victory in Wisconsin means the Illinois senator has swept every state nominating contest since "Super Tuesday" in early February, when nearly half the states picked Democratic and Republican presidential candidates.
The victories have given him an edge in pledged delegates to the party's nominating convention this summer, leaving New York Senator Clinton needing dominant victories in the big-state contests of Ohio and Texas on March 4 to catch up.
Republican front-runner John McCain also won the Wisconsin primary on Tuesday, taking another big step toward becoming his party's nominee in November's presidential election.
McCain, an Arizona senator, beat his last remaining major rival, former Arkansas Gov. Mike Huckabee, to expand his huge and essentially insurmountable lead in delegates.
"Thank you Wisconsin for bringing us to the point where even a superstitious naval aviator can claim with providence and humility that I will be our party's nominee for president," McCain, a former Navy fighter pilot and Vietnam prisoner of war, told supporters in Columbus, Ohio.
Democrats in Hawaii, where native Obama is a heavy favourite, also vote on Tuesday.
Up for grabs in the two states are a combined 94 delegates to the August convention that selects the Democratic presidential nominee in November's election. Obama has a slight lead in pledged delegates won in state presidential contests.
Democrats open their caucuses for presidential preference voting in Hawaii at 7pm HST (6pm NZT on Wednesday).
In the Democratic race, Obama and Clinton already have turned their attention to March 4 contests in two of the biggest states, Ohio and Texas, which have a rich lode of 334 convention delegates at stake.
Clinton is the early favourite in both, although one public opinion poll in Texas on Monday showed the race in a statistical dead heat. Clinton campaigned in Ohio and Obama in Texas on Tuesday.
Wisconsin has a large population of the blue-collar workers and rural voters who have been a big part of Clinton's constituency, and few of the black voters who have overwhelmingly supported Obama.
The primary also is an open contest allowing participation by Republicans and independents, not the small, closed caucus states where Obama has performed well.
Republicans in Washington state also hold a primary, which is the second half of their two-tiered nominating contest. The state's Republicans held a caucus on February 9, won narrowly by McCain.
The voting ends for Washington Republicans at 8pm PST (5pm NZT on Wednesday).
- REUTERS