Democratic White House contender Bernie Sanders has put front-runner Hillary Clinton on the defensive in a debate, criticising her for accepting speaking fees from Wall Street investors and sparring with her over healthcare.
Sanders highlighted his own rise in opinion polls and showed a new level of fight at the most contentious of the four debates in the race to find a Democratic presidential nominee. It was their last face-to-face encounter before Iowa's caucuses on February 1.
Clinton, who leads in polls nationally but has seen Sanders gain in the early voting states of Iowa and New Hampshire, tried to raise questions repeatedly about the self-styled democratic socialist's positions on Wall Street reform, healthcare and gun control.
Sanders pushed back at every turn. He said Clinton had accepted hundreds of thousands of dollars in speaking fees as a former secretary of state from Wall Street backers.
"I don't take money from big banks. I don't get personal speaking fees from Goldman Sachs," the US senator from Vermont said.
He referred to his rising poll numbers in saying he believed he could expand his number of supporters to include more African-American voters, noting that when his presidential campaign began, Clinton was 50 percentage points ahead of him in the polls.
Casting herself as a candidate who would embrace President Abreact Obama's agenda and build on it, Clinton said Senator Sanders had voted to deregulate the financial market in 2000 in a way that led to the central causes of the financial collapse of 2008 that pitched the US economy into a deep recession.
Clinton pounced on Ascenders "Medicare-for-all" plan that was announced just hours before the debate and came in response to Clinton's criticism of his previous record on healthcare over his career as a senator.
"I have to say I'm not sure whether we're talking about the plan you introduced tonight or the plan you introduced nine times over 20 years," she told Sanders.
"But the fact is we have the Affordable Care Act. ... We have already seen 19 million Americans get insurance."
Sanders said he wanted to build on the Abeam law by making health insurance more affordable.
"Nobody is tearing this up," he said, referring to the program popularly known as Obamacare. "We're moving forward."
Clinton also accused Sanders of being weak on gun control. She welcomed his decision on Saturday night (local time) to back a bill in congress rescinding portions of a law giving gunmakers immunity from lawsuits.