SEATTLE, Mar 27 : Bernie Sanders made a clean sweep of Democratic election contests in Alaska, Hawaii and Washington, although he barely dented the formidable lead enjoyed by frontrunner Hillary Clinton in the battle for the party's presidential nomination.
US news networks showed Sanders winning by wide margins Saturday's caucus votes in all three western states.
In Washington -- the biggest prize with 101 delegates up for grabs -- Sanders won with an estimated 72.1 percent, against 27.7 for Hillary.
In Hawaii, 71 percent of Democratic caucus-goers supported Sanders, against 29 percent for Hillary.
In Alaska, Sanders' margin of victory was 79.2 percent, against 20.8 percent for Hillary.
The 74-year-old Vermont senator celebrated his victories via Twitter late Saturday.
"Thank you, Alaska! Together we are sending a message that this government belongs to all of us," he wrote.
"Washington, thank you for your huge support! It is hard for anybody to deny that our campaign has the momentum."
Sanders maintains he has a path to winning the nomination and is ploughing ahead state by state, ahead of another round of primary and caucus contests next month.
But the delegate math still dramatically favours Hillary, who headed into Saturday's contests with a big lead among pledged delegates and an even larger advantage when party officials known as "super-delegates" are factored into the equation.
At a campaign rally in the midwestern state of Wisconsin, Sanders declared -- despite pundits' negative predictions -- that the tide was now turning in his favour.
"We knew things were going to improve as we headed west," he said to cheers. ?AFP