Sanders plays down Clinton's hold over voters in Iowa home stretch

On the last day of campaigning before the Iowa caucuses, Bernie Sanders mounted a last-minute challenge to Hillary Clinton's slim poll lead.

US Democratic presidential candidate Bernie Sanders speaks at a campaign rally in Waterloo, Iowa January 31, 2015.  [Photo/Agencies]

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Rejecting suggestions that the Democratic party leadership was wary of his nomination because they are fearful of his proposals to raise taxes, Sanders told NBC's Meet the Press it was not his healthcare and tax proposals that would cause problems in the general election.

"I think, in fact, Hillary Clinton will be the problem," he said.

Sanders said his proposals would save middle-class families thousands of dollars a year on their healthcare costs.

"Most people tell me, yes, they would be happy to pay $1,000 more in taxes if they're paying $5,000 less in healthcare premiums," he said, vowing to take on drug companies "who are ripping us off" and to guarantee healthcare to all people, and thereby to "do what every other major country on earth is doing".

A Des Moines Register-Bloomberg poll released on Saturday found Clinton with 45% of Democratic support and Sanders with 42%.

Sanders acknowledged that success in the caucuses on Monday – as the threat of fierce winter weather hovers over the state, though a blizzard is forecast only for Tuesday – will depend on a healthy turnout of young supporters, as it would in a general election should he win the nomination.

He said his campaign was "generating excitement and energy that will result in a high voter turnout. Republicans win when voter turnout is low. Democrats win when voter turnout is high. I think our campaign is raising issues about a rigged economy and a corrupt campaign finance system."

Later on Sunday the Sanders campaign released financial figures, saying it had raised $20m in January, mostly from donations of no more than $27. The campaign's 3.25 million individual contributions are a record for any presidential candidate.

Sanders' campaign manager, Jeff Weaver, claimed the Register poll showed momentum on the senator's side.

"Our campaign has come a very long way in eight months. In late May, according to the Register/Bloomberg poll, we were down by 41 points. Today we are virtually tied," he told the Washington Post.