Hillary Clinton has attacked her main rival Bernie Sanders over US gun laws at the Democratic presidential debate.
When asked if the Vermont senator was strong on gun control, she said, “No, not at all,” before vowing to go after the makers of guns used in shootings.
Mr Sanders also attacked Mrs Clinton, saying her support for a no-fly zone in Syria would create “serious problems”.
His rallies have drawn big crowds and he has challenged Mrs Clinton’s frontrunner status in some key states.
Mrs Clinton and Mr Sanders dominated the debate. The three other candidates on stage in Las Vegas – former Maryland Governor Martin O’Malley, former Virginia Senator Jim Webb and former Rhode Island Senator Lincoln Chafee – struggled to make headway.
- Biggest applause of the night to Mr Sanders when he said the country was “sick” of hearing about Mrs Clinton’s email controversy
- The self-described democratic socialist railed against the wealth going to the “top 1%” and lauded Denmark as an example
- Former first lady said she would stand up to “bully” Russian President Vladimir Putin
- But she was on the defensive for supporting the Iraq War and backing a no-fly zone in Syria
The two main candidates were sharply divided over gun laws, in the wake of a mass shooting at a college campus in Oregon.
When Mrs Clinton said her rival was not tough enough, she was referring to him voting in 2005 for a measure to give gun manufacturers immunity from lawsuits by shooting victims.
The two also argued over the merits of capitalism.
Mr Sanders called for a “political revolution”, arguing that “Congress does not regulate Wall Street. Wall Street regulates Congress”.
But when he suggested that the US should look to Nordic countries because of “what they have accomplished for their working people”, Mrs Clinton responded: “We are not Denmark. I love Denmark. We are the United States of America.
“I’m a progressive, but I’m a progressive who likes to get things done,” she said.
Analysis: Kim Ghattas, BBC News, Las Vegas
This was all about Bernie Sanders and Hillary Clinton. And both their campaigns were incredibly happy with the candidates’ performance.
Mr Sanders’ campaign manager told me he demonstrated he was the most electable Democrat in a general election. A Clinton aide told me the former secretary of state’s performance was “awesome”.
If the other three candidates had hoped this was their opportunity for a breakthrough on the national stage, they failed, especially Mr Chafee and Mr Webb. It raises the question of how much longer they’ll stay in the race.
With far fewer candidates sharing the stage, there was more opportunity for a substantive debate than at the Republican events so far. But it was also more lively than most anticipated, in part due to the skills of the moderator but also because on a few issues, the candidates did really spar – on guns, Wall Street, and the use of US military power.
Vice-President Joe Biden is still considering a run for the White House and did not make a last-minute entry on to the stage, as his supporters hoped.
Mrs Clinton has seen her support wane amid questions about her use of a private email account when she served as US secretary of state, a move she now calls a mistake.
However, she was unfazed during the debate when Mr Chafee questioned her credibility, refusing to respond when invited.
Mr Chafee said twice that one of his strengths was that he had never had a political scandal. Mr O’Malley defended his record as mayor in Baltimore, where there were riots this year, while Vietnam veteran Mr Webb said his military service gave him leadership skills.
The candidates tried to distinguish their debate from those of the Republicans, where candidates took a tougher stance on immigration and spent more time discussing social issues like abortion and gay marriage.
Mr O’Malley used his 90-second closing speech to say the Republican debates were lessons in intolerance.
Republican candidates took to Twitter to offer reactions. Jeb Bush said Mrs Clinton had “just told you she has no interest in changing direction. I sure will.” Frontrunner Donald Trump said he found the debate “a little sad!”, and that candidates appeared “very scripted”.
Fifteen Republicans are vying to be the party’s White House nominee in 2016.
Iowa will be the first state to choose its candidate from each party in February, then other states hold primaries in the following weeks and months.
By next summer, each party will have a presidential nominee who will do battle in the race for the White House.
Votes will finally be cast in November 2016.