DETROIT • United States senators Elizabeth Warren and Bernie Sanders offered an unabashed defence of their progressive policies during a Democratic presidential debate, as their more moderate rivals criticised their proposals as unrealistic and politically untenable.
The debate frequently pitted the two senators against the other eight candidates on stage, with healthcare and immigration policy highlighting the divisions between the two camps.
On the first night of back-to-back debates on Tuesday, Democrats were united in stressing the urgency of defeating Republican President Donald Trump in the November 2020 election.
But they delivered bruising critiques of their party rivals' positions as detailed policy disagreements dominated the nearly three-hour event.
The dispute between the moderate and liberal wings of the Democratic Party highlighted the central question of the nominating contest: Which candidate in the field of more than two dozen would be best positioned to beat Mr Trump next year?
The moderate wing, led at times by Montana Governor Steve Bullock, argued that Democrats risk losing voters after moving too far to the left in the opening debate in June in Miami.
In contrast, progressives argued that their policies would excite voters and allow them to draw a distinct contrast to Mr Trump.
Mrs Warren rebuked former US Representative John Delaney, who often played the role of foil to the progressives during the debate, firing back at his criticism of her policies.
"I don't understand why anybody goes to all the trouble of running for president of the United States to talk about what we really can't do and shouldn't fight for," she said.
Mr Sanders also bristled at arguments that his proposals could not be realistically achieved, saying: "I get a little bit tired of Democrats afraid of big ideas. Republicans are not afraid of big ideas."
As the front runners in polls among the candidates debating on Tuesday, Mr Sanders and Mrs Warren vowed not to attack each other, but needed to distinguish themselves in their bid to gain ground on the race's leader, former vice-president Joe Biden.
Instead, both senators often found themselves teaming up to defend policy positions they share instead of drawing contrasts.
Mr Biden and rival Kamala Harris were expected to stage a rematch of June's explosive debate confrontation during Round 2 yesterday, with a re-energised Mr Biden promising a more aggressive approach.
On the second of back-to-back nights of Democratic debates, Mr Biden was slated to be flanked at centre stage by Ms Harris and Mr Cory Booker.
Both US senators are the most prominent black contenders in a Democratic nominating contest in which race has played a prominent role.
Mr Biden has for weeks been engaged in an escalating fight with Ms Harris and Mr Booker for the support of black voters, a vital constituency in the Democratic nominating battle.