The Hillary Clinton campaign and its backers in the media are increasing the pressure on Vermont Senator Bernie Sanders to end his campaign for the Democratic Party presidential nomination. Clinton campaign aides waged a full-court media campaign Monday, effectively reneging on a previous agreement to debate Sanders in April and May, declaring that Sanders had violated previous pledges not to engage in “negative” advertising, and claiming that Clinton would clinch the number of delegates required for the nomination by the end of April.

Chief pollster Joel Benenson told CNN that any future debate participation by Clinton would depend on the “tone” set by Sanders in his criticism of Clinton. He was responding to a public letter sent by the Sanders campaign on the weekend reminding Clinton of her agreement to debate Sanders in April, probably in New York City, in advance of the New York primary April 19.

Clinton adviser Karen Finney told CNN Tuesday that “negative attacks” by the Sanders campaign had put the debate deal in question. She was referring to Sanders’ continuing attacks on the role of big money in Democratic and Republican politics and Clinton’s numerous appearances before Wall Street audiences, where she received six-figure speaking fees. The Clinton campaign, for obvious reasons, does not want her close ties to Wall Street to be highlighted during a campaign in New York state.

Benenson also claimed that Clinton was “dominating” the Democratic contest, despite losing, by double-digit margins, six of the last seven contests—Utah, Idaho, Washington State, Alaska, Hawaii and Democrats abroad—winning only in Arizona. Sanders has cut Clinton’s lead among elected delegates to about 240 and is favored to win the Wisconsin primary April 5 and the Wyoming caucuses April 9.

Benenson maintained that Clinton would win New York, the state she represented in the US Senate, on April 19, and win enough delegates in a string of East Coast states April 26—Maryland, Delaware, Pennsylvania, Connecticut and Rhode Island—to obtain the 2,382 convention delegates required for nomination. “He’s going to contest these states, we’re going to contest these states, but the truth is that after April 26 there is just not enough real estate for Senator Sanders to contest the lead that we’ve built,” the Clinton aide said.

This tendentious accounting assumes both Clinton victories in all these states and the support of the vast majority of unelected superdelegates—the party officials and office-holders who have automatic votes at the Democratic National Convention.

The premature claims of victory were bolstered by supposedly “objective” reports in pro-Clinton media outlets like the New York Times, which published an analysis purporting to prove that a Sanders victory had a vanishingly small mathematical chance. The analysis made no assessment of the impact of recent Sanders victories or the inability of the Clinton campaign to win support from young people and large sections of the working class.

The real state of affairs in the Clinton camp, however, is suggested by an article in the Wall Street Journal Sunday reporting that leading Democrats were looking to Vice President Joseph Biden to come to Clinton’s aid, offsetting what the newspaper delicately referred to as “Mrs. Clinton’s vulnerabilities,” particularly with “working-class whites.” The newspaper noted that Clinton had “lost this group to Mr. Sanders by 25 percentage points in Michigan, by 15 points in Ohio and 22 points in North Carolina, exit polls show.”

In appearances on several Sunday television interview programs, Sanders suggested that his campaign would now attempt to gain a hearing from superdelegates who had previously committed themselves to Clinton, arguing that his own campaign would be more effective in mobilizing voters for the Democratic Party, not only in the presidential race, but also in congressional and gubernatorial races further down the ballot.

Sanders reiterated his attacks on “big money” support to Clinton, singling out a fundraising dinner to be hosted by the actor George Clooney, where supporters would pay as much as $353,000 apiece to sit with Clinton and Clooney at the head table.

“It is obscene that Secretary Clinton keeps going to big money people to fund her campaign, and it’s not just this Clooney event,” Sanders told CNN. While not criticizing Clooney for his involvement, Sanders said that “the people who are coming to this event have undue influence over the political process.”

Polls released over the past ten days suggest that Clinton’s once huge lead over Sanders is closing, if not entirely erased. An NBC News/SurveyMonkey online tracking poll released Tuesday found that Clinton’s lead over Sanders had been cut in half over the past week, from a 12-point lead, 53 percent to 41 percent, to a 6-point lead, 49 percent to 43 percent. A separate survey by Bloomberg showed Sanders with a one-point lead over Clinton, 49 percent to 48 percent.

A CNN/ORC poll last week showed Sanders defeating Republican frontrunner Donald Trump by 20 points in a general election contest, compared to a 12-point Clinton lead over Trump.

The crisis of both of the major capitalist parties was signaled by another survey, this time by Fox News, which found that three of the four leading candidates for the Democratic and Republican nominations, Clinton, Trump and Texas Senator Ted Cruz, had the highest personal unfavorability ratings in the history of public polling on that question.

Only 36 percent of those polled had a favorable opinion of Cruz, an ultra-reactionary who is appealing particularly to Christian fundamentalists, while 53 percent had an unfavorable opinion, for a net rating of negative 17. Clinton’s margin was worse, with 39 percent positive and 58 percent negative, or negative 19. Trump was even lower, with only 31 percent positive and 65 percent negative, or negative 34.

In other words, a Clinton-Trump contest would pit two deeply unpopular candidates against each other—the personification of the corrupt US political establishment versus the crude gangster billionaire—with each side seeking to convince the American public that the other was more repugnant.

The role of Sanders, who has won wide support particularly among young people and sections of the working class because of his avowed “socialism,” is to provide a political facelift to the Democratic Party, one of the twin parties of Wall Street and US imperialism.

This will not be an easy task. According to a UCLA/LA Times poll of voters in California, released Monday, 20 percent of likely Sanders voters said they would not support Clinton in November if she won the nomination. Of those who said they would vote for Clinton, 45 percent said they would do so “reluctantly,” compared to only 35 percent who said they would do so with any enthusiasm.

Sanders’ nominal “socialism” is little more than watered-down liberalism of the 1960s, with no call for social ownership of the means of production and not a shred of opposition to American imperialism and its program of global aggression.

He himself has repeatedly pledged to support Clinton if she is the nominee. The corporate ruling elite has long since taken the measure of the Vermont senator and regards him as a useful political tool, providing he continues to keep his anti-Wall Street rhetoric within bounds. As James Traub noted in the New York Times Sunday, “While labeling himself a democratic socialist, [Sanders] is almost elaborately respectful of his political rival Hillary Clinton and the political process… Through figures like him, American democracy permits intense passions to be expressed, contained and, perhaps, vented.”