Bernie Sanders emphasizes differences between himself and Hillary as polls tighten
Senator Bernie Sanders of Vermont speaking at a town meeting at the Phoenix Convention Center in Phoenix, Arizona (Gage Skidmore/Flickr)

After a new poll showed Bernie Sanders trailing Hillary Clinton in Iowa by only seven points, the Vermont senator seized a chance to differentiate himself from the establishment favourite for the Democratic presidential nomination.

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Appearing on CNN, Sanders listed a number of his policy positions, including on Wall Street reform, climate change and entitlements. He repeated after each one: “That is not Hillary Clinton’s position.”

There was some good news for the former secretary of state on Sunday, however. Senator Jeanne Shaheen said she would confirm her endorsement of Clinton at an event in New Hampshire, another early voting state, next week.

The Iowa poll, carried out by the Des Moines Register and Bloomberg Politics , was released late on Saturday. It showed Clinton leading among likely Democratic voters in the early voting state but down 20% on her position in the last such poll in May. It is the first time she has polled well under 50% in the state in this campaign cycle.

Sanders attracted 30% support, one-third of Clinton’s previous support having transferred allegiance.

Vice-president Joe Biden, not yet a declared candidate, scored 14%. Were Biden not to run, the Register said, Clinton would only climb to 43%.

Asked on CNN how he would take on “the billionaire class”, a central target of his campaign stump speeches, in ways Clinton would not, Sanders said: “I believe that, when you have so few banks with so much power … you have got to break them up. That is not Hillary Clinton’s position.

“I believe that our trade policies … have been a disaster. I am helping to lead the effort against the Trans-Pacific Partnership. That is not Hillary Clinton’s position.” Sanders also said that he would “defeat” the Keystone pipeline, expand social security and raise the minimum wage to $15, all things Clinton would not do.

Touching on foreign policy, which has not been a focus of his campaign, he said: “I voted against the war in Iraq. Hillary Clinton voted for it.”

In a subsequent appearance on ABC, Sanders was asked about his votes against military force in Iraq and in Syria, as well as the first Gulf War. In 2001, after 9/11, he voted in support of the invasion of Afghanistan.

“There are times when you have to use military force,” he said, “no question about it. I am prepared to do it, but that is the last resort, not the first.

“I think historically, in too many instances, the United States has gone to war often unilaterally when we should not have.”

Clinton is beset by Republican pressure over her use of a private email server while secretary of state. The former Pennsylvania governor Ed Rendell, a longtime Clinton ally, added to such discomfort this week when he said her campaign had handled the issue “ poorly, maybe atrociously, certainly horribly ”.

On Sunday the New Jersey governor Chris Christie , one of 17 candidates for the Republican nomination, told Fox News Sunday “no one is above the law”.

Christie added that Clinton should face prosecution if investigators, including the FBI, established that she mishandled diplomatic emails.

The Iowa pollsters, however, reported a majority (61%) of likely Democratic caucus-goers saying the email scandal was not important to them.

The Register/Bloomberg poll was carried out after the Iowa State Fair, a key event around which both Clinton and Sanders campaigned . Sanders, a self-described democratic socialist who sits in the Senate as an independent, continued to attract large crowds.

Of the other candidates for the Democratic nomination, former Maryland governor Martin O’Malley (3%), former Virginia senator and Reagan navy secretary Jim Webb (2%) and former Rhode Island governor Lincoln Chafee (1%) all scored less than “uncommitted” (6%) and “not sure” (8%).

O’Malley did draw a crowd of 400 people in Iowa on Sunday, at Grinnell College. He would not, however, qualify for the Iowa caucus if it were held today. The threshold for participation is around 15% support.

Related: Martin O'Malley accuses DNC of 'rigging' primary process in Clinton's favour

Sanders was also asked on CNN if he agreed with O’Malley’s angry contention that by staging only four primary debates, the Democratic National Committee was attempting to “rig” the nomination process for Clinton.

“I think rigging is a strong word,” Sanders said, although he added that he would “love to see more debates”.

Pressed on the restriction of debates by the DNC, he said: “I think that that is dead wrong, and I have let the leadership of the Democrats know that.”

On the Republican side of the ledger , the Register/Bloomberg poll showed the real-estate mogul Donald Trump leading the 17-strong field with 23%, to 18% for another outsider candidate, the neurosurgeon Ben Carson.

Texas senator Ted Cruz and Wisconsin governor Scott Walker scored 8% each, ahead of Senator Marco Rubio and former governor Jeb Bush, long seen as the likeliest challenger to Clinton in a general election. The two Florida politicians both attracted 6% support. © Guardian News and Media 2015