Analysis:: After New York battle, Clinton and Sanders temper their vitriol. But there are signs it won’t last

Reporting from Philadelphia —  In the wake of Hillary Clinton’s expansive win in the New York primary, both she and challenger Bernie Sanders face a freighted decision: whether, and how, to pull back on rhetoric that has grown sharper and nastier in recent weeks as they battle for the Democratic nomination.

The choices, whether to lay down arms or continue strafing, would seem to be simple. But the stakes are so high that the strategic imperatives are complicated.

Both candidates are seeking delegates in Pennsylvania and in four other states Tuesday. But neither wants to risk alienating voters by coming off as too negative. Both candidates — particularly Clinton, the leader in delegates with a far better shot at the nomination — are looking at the difficulties inherent in unifying a fractured party in November.

At least initially, both candidates appeared to be muting their criticisms, keeping them squarely in a comparative “I opposed, my opponent didn’t” vein. But the sentiment was fleeting on Sanders’ side.

In her first post-New York appearance in Philadelphia on Wednesday, Clinton reminded a group assembled in a Baptist church of Sanders’ vote to give legal immunity to gun makers and sellers in a shooting involving their weapon.

“That’s one of the big differences between me and Sen. Sanders,” she said, repeating in milder form one of the main thrusts of her New York campaign.

“There’s been a lot of talk in this campaign and the primary campaign about the power of certain interests in this country,” she said, referring to Sanders’ criticism of her ties to Wall Street, “… but there is no more powerful lobby than the gun lobby, none.”

Sanders, in his first campaign event after New York, a rally on Thursday in Scranton, Pa., was similarly careful with his words.

In an hourlong speech, he made no mention of Clinton’s top-dollar speeches to Wall Street and no demands that she release transcripts of them. He didn’t talk about the millions of dollars that super PACs have raised on her behalf from Wall Street nor of additional money she has accepted from other special interests. All of those complaints have had prominent roles in Sanders’ speeches for weeks.

Sanders noted several areas in which he and Clinton disagree — over the minimum wage, trade agreements, fracking and lifting the income cap to better fund Social Security. But his comparisons, like Clinton’s, were more bland than they have been.

“I opposed all these trade agreements; Secretary Clinton supported most of them. That is a big difference,” he said in what served as Thursday’s template.

But hours later in Reading, Pa., Sanders was back to mocking her Wall Street speeches and the millions of super PAC dollars she has received from groups of whom he disapproves.

The tone in any campaign, this one included, can alter at any time; in recent weeks, an offhand comment by one candidate has prompted a heightened response from the other, escalating into a cascade of insults. Clinton and Sanders and their teams have blamed each other for escalating the negativity — and thus each had insisted the other needed to take the first step to change the tone.

“Bernie always wanted to have just an up-or-down debate on the issues,” said Sanders’ chief strategist, Tad Devine. “If they want that, they can have it. If they’re going to run the kind of campaign they ran in New York, there’s going to be a tough response from Bernie. He’s not just going to take it.”

The Sanders campaign expected better results in New York, where Clinton won by 16 points. That big-state victory gave her a net gain of 33 delegates, nearly wiping out Sanders’ net gain of 45 delegates in his last five victories. That points to a persistent problem for Sanders: His losses in highly populated states, combined with the proportional way Democrats allocate delegates, have made it tough for him to close Clinton’s advantage of far more than 200 pledged delegates.

Sanders’ campaign manager, Jeff Weaver, said Tuesday night on MSNBC that the candidate would spend the period before the July convention attempting to flip superdelegates, party leaders who have agreed to support Clinton. That effort, an acknowledgment that Clinton will win more pledged delegates, would extend the campaign season beyond the last big primaries in June, heightening the tension between the candidates.

But Devine said that finishing with more pledged delegates remains the goal. He said the campaign was looking forward to “a brilliant winning streak through California and New Jersey,” which both vote on June 7.

“We don’t do this unless we win,” he said. “We have to win next week, we have to consistently win in May, and we have to have big wins in May.”

In the meantime, prominent Sanders supporters were sharply divided about how to navigate the course ahead.

All year long, exit polls have shown that Sanders supporters are less willing to consider voting for Clinton in November than her supporters are about voting for him. The tone of the New York campaign, if anything, heightened concerns about the willingness of Sanders supporters to back Clinton if, as the odds have it, she becomes the nominee.

Sanders outraged Clinton’s side by declaring her unqualified for the presidency because of her vote for the Iraq war, her campaign fundraising and her links to Wall Street. Clinton outraged Sanders by hitting him hard on the gun immunity vote. Robert Reich, a UC Berkeley professor who is a prominent Sanders backer and served as President Clinton’s first secretary of Labor, suggested Wednesday that both teams retreat.

“I want to urge Bernie supporters to tone down negative characterizations of Hillary and Hillary supporters to do the same with regard to Bernie,” he wrote in a Facebook post. “I know both candidates personally. Both are thoughtful and dedicated people who care deeply about this nation. Either of them would be a thousand times better president than any of the Republican candidates.

“It’s important that we not jeopardize that future joint effort through excessive divisiveness now,” he said.

But another key Sanders supporter insisted that Sanders should campaign unrelentingly — and she did so in language sure to inflame the Clinton forces. Speaking of the New York loss, RoseAnn DeMoro, executive director of National Nurses United, a union that was an early Sanders endorser, said it “makes us far more determined because the election was essentially stolen.”

Her argument, seconded by Sanders in Scranton on Thursday, was that independents should have been allowed to vote in the New York primary, even though they are not Democratic Party members.

“If the independents were able to vote in New York, Bernie would have won,” she said. “Anywhere where the vote was fair, Bernie won. We are not going to be deterred by a stolen, corrupted system.”

She characterized Sanders as treating Clinton with “kid gloves” and said “she is great at being the victim. She is one of the most aggressive females I’ve ever watched, and she has a tendency to pose as a victim.”

“We plan on beating Clinton,” she added. “This isn’t Kumbaya time.”

The immediate news isn’t good for Sanders in Pennsylvania, the largest of the five states that will vote on Tuesday.

A Monmouth University poll found Clinton leading in the state, 52% to 39%. It fits the profile of places where Clinton has done well: diverse and bigger states where primaries are limited to Democrats.

How they choose to contrast each other’s views will affect not only the primary campaign but also the general election — particularly if Clinton, already suffering from high unfavorability ratings, chooses or is forced to campaign in a highly negative way to secure the nomination.

cathleen.decker@latimes.com

Times staff writers Mark Z. Barabak in New York and Noah Bierman in Philadelphia contributed to this report.

Follow me on Twitter @cathleendecker

For more on politics, go to latimes.com/decker

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