US Republicans are trading blows in a fiery presidential debate in Boulder, Colorado, condemning the media, Democrats and each other.
Frontrunners Donald Trump and Ben Carson, with no political experience, have been under attack.
"We can't elect someone who doesn't know how to do the job," said Ohio Governor John Kasich.
Mr Carson, a retired neurosurgeon, has edged past the New York businessman Mr Trump in national polls.
Mr Trump was riled by one of the first questions - he was asked if his economic plan was a "comic-book version" of a presidency campaign.
Eight other candidates, who remain a long way behind in the polls, are sharing the stage with the two frontrunners.
Mr Kasich said other candidates' proposed policies - like Mr Carson's tax plan and Mr Trump's plan to build a wall on the Mexico border - were "fantasy".
Former Florida Governor Jeb Bush and Florida Senator Marco Rubio traded barbs, with Mr Bush saying the people of Florida deserved a senator devoted to representing them, not one busy running for president.
"Someone has convinced you that attacking me is going help you," Mr Rubio responded.
The lowest-polling Republican candidates - Louisiana Governor Bobby Jindal, former New York Governor George Pataki, former Pennsylvania Senator Rick Santorum and South Carolina Senator Lindsey Graham - squared off in an early debate.
Mr Graham, the South Carolina senator, got the most laughs, especially when he attacked the top two Democrat candidates, former Secretary of State Hillary Clinton and self-described socialist Bernie Sanders.
"The number one candidate says she was flat broke even though she spent eight years in the White House," said Mr Graham.
"The number two guy went to the Soviet Union on his honeymoon and I don't think he ever came back."
Primary voting begins in February in Iowa, where Mr Carson also leads the polls.
