SEATTLE (AFP) - A resilient Bernie Sanders went gunning for Hillary Clinton's commanding lead as Alaska, Hawaii and Washington states took their turn voting on Saturday in the Democratic presidential nominating contest.
Defeat to Clinton in the trio of western caucuses was unlikely to deal a fatal blow to the chances of the Vermont senator, a self-described democratic socialist, but opportunities are running out if he is to pull off an unlikely upset and seize the Democratic nomination.
Sanders, 74, gave a rousing rendition of his standard stump speech late on Friday in Seattle, Washington, just hours ahead of the caucus there, railing against police brutality, a too-low minimum wage, and soaring student debt and other ills.
"Real change historically always takes place from the bottom on up when millions of people come together," Sanders said to applause and cheers from the crowd in the city's Safeco baseball stadium. "We need a political revolution!"
Sanders also needs success Saturday because Clinton, the long-time frontrunner, has a comfortable lead in the delegate race with 1,711, including super-delegates who are unelected by voters, compared to 952 for Sanders, according to a CNN count.
To win the Democratic nomination, 2,383 delegates are needed.
On the campaign trail, Clinton, the former secretary of state, has already shifted her focus toward November's general election.
She delivered a somber counterterrorism speech on Wednesday in the aftermath of deadly attacks in Brussels, using it as an opportunity to launch vigorous assaults on Republican candidates Donald Trump and Ted Cruz and warn their "reckless" foreign policies would harm US interests.
"We need to rely on what actually works, not bluster that alienates our partners and doesn't make us any safer," she said.
But Sanders has refused to throw in the towel, repeatedly stressing that his grassroots campaign is heading all the way to July's nominating convention in Philadelphia.
Washington is Saturday's biggest prize with 101 pledged delegates up for grabs. When Sanders brought his message of "political revolution" to a Seattle arena last Sunday, an estimated 17,000 people showed up.
The Pacific island state of Hawaii, birthplace of President Barack Obama, has 25 delegates at stake. Remote Alaska has 16.
There has been little reliable polling in the three states, but in Washington Sanders can take comfort in previous results.
Bill Clinton placed fourth in Washington in the 1992 nominations race, while Democrats there overwhelmingly backed Obama over Hillary Clinton in 2008.
Saturday's three contests are caucuses, essentially neighborhood meetings where voters can discuss political platforms and debate the merits of the candidates.
Since they generally require voters to show up in person rather than mailing primary ballots, the format favours Sanders, whose supporters have consistently shown more grassroots enthusiasm.
His campaign pointed to a new poll released on Thursday that shows Clinton, who entered the race as the Democrats' overwhelming favorite, deadlocked with Sanders.
A Bloomberg Politics national poll found Sanders actually inching ahead of Clinton, 49 to 48 per cent, among Democrats who voted or are likely to vote in the nominating contests.
A series of recent polls has shown Sanders consistently doing better than Clinton against Republicans Trump, Cruz and Ohio Governor John Kasich.
Millennials and first-time voters have been flocking to Sanders's message of economic equality, universal health care, and his call to reduce the influence of billionaires on the campaign finance system.
But the delegate math still dramatically favors Clinton.
According to RealClearPolitics poll averages, in the remaining states with the three largest delegate allocations - California, New York and Pennsylvania - Clinton leads Sanders by nine points, 34 points and 28 points respectively.
Despite that, Sanders had his supporters on their feet on the eve of voting, especially when during a rally that drew 11,000 in Portland, Oregon, a bird popped up and landed on the podium right in front of him as he addressed the crowd.
"I think there may be some symbolism in this," said an amused Sanders, after the bird spent a few moments with him before flying off.
"I know it doesn't look like it, but that bird is really a dove asking us for world peace," he added, bringing the crowd to its feet once more.
"No more wars!"