At a rally in Springfield, Ore., Democratic presidential candidate Bernie Sanders took aim at Republican rivals April 28, saying if you look at their plans, "it is hard to imagine anybody voting for that agenda." (Reuters)

SPRINGFIELD, Ore. -- Two days after his bruising losses in the final East Coast primaries, Sen. Bernie Sanders (I-Vt.) flew west and found refuge. Down the road from Eugene, site of the University of Oregon's biggest campus, Sanders filled a riverside park with thousands of supporters, some of whom waited in a mile-long security line. More than a few hoisted paintings or cartoons of the bird that landed on Sanders's podium during his last visit to the state.

Yet as he'd done since Tuesday, Sanders trimmed some of his criticism of Hillary Clinton. The crowd still cheered when Sanders said he'd challenged "the entire Democratic establishment and the most powerful political organization in this country." But Sanders did not give them as many cues to jeer Clinton as he'd given audiences in New York and Pennsylvania. He shot most of his ammo at Republicans, and a "fringe" agenda to let more money into politics and lower taxes for the rich.

Over the course of an hour, Sanders mentioned his policy differences with Clinton just three times. First, he said that he'd opposed the "bad trade deals" that she'd supported. He went on to invite Clinton to support a national ban on fracking -- but did not, as in New York, criticize her State Department for promoting fracking abroad.

Finally, toward the end of the speech, Sanders referred somewhat generically to Clinton as part of a political class that doubted the power of voters to make change.

"The establishment will always tell us that real change is impossible," Sanders said. "It can't happen! Don't think big, think small, think incrementally. You really have no power!"

When a voter yelled "bull----," Sanders laughed.

"I like that," he said. "Now, I myself can't phrase it exactly like that. But that's not bad."

Democratic presidential candidate Bernie Sanders at a rally in Springfield, Ore., on Thursday, April 28, 2016. (AP Photo/Ryan Kang)

Supporters of Sanders, who have bristled when Clinton allies suggest the senator should change his "tone," may need to get used to it. In an interview with The Washington Post's John Wagner on Wednesday, Sanders said he would continue contrasting his views with Clinton's, but said more about the changes his delegates could force to the Democratic platform.

In the interview, and in Springfield, Sanders called for the party to allow independents to vote in primaries. (In the past two weeks, Sanders's only win has come in Rhode Island, where Clinton won the Democratic vote but independent voters crossed over for the Vermont senator.)

In both forums, Sanders also suggested that the superdelegates who pad Clinton's lead -- and who, if current voting trends continue, will secure her a majority within the next six weeks -- should look at polls that have him winning the general election.

"I think what a lot of delegates will tell you, maybe off the record, if not now on the record, if we look at it objectively, if you look at virtually all the polling out there, state polling, national polling, Bernie Sanders defeats Donald Trump, in almost every instance by a larger margin than Hillary Clinton," Sanders told The Post.

In Springfield, Sanders called the polls the "most important" piece of information about his candidacy.

"I hope the delegates going to the Democratic convention pay heed to this," he said. "In every national poll done in the last month, we are defeating Donald Trump by much greater margins than Secretary Clinton."

Before getting to Oregon, Sanders revealed that his campaign was parting ways with 225 staffers and pivoting to California. But nothing has changed in Oregon, where Sanders's campaign opened its second office, in Portland, just weeks ago. And in interviews in both Springfield and Portland, Sanders supporters were universal in their expectation that the Democratic primary would go to a contest at the convention in Philadelphia.