Millions of US voters are casting ballots in a series of high-stakes Super Tuesday primary contests for the Democrats.
Vermont Sen Bernie Sanders began the day as the Democrats’ undisputed presidential front-runner, backed by a coalition of energised liberals, young voters and Latinos.
The progressive was fighting to beat back the sudden rise of former vice president Joe Biden, who seized a wave of new support from some of his former Democratic presidential rivals just hours before polls opened in his quest to lead the party’s moderate wing.
The clash between the two men, each leading coalitions of disparate demographics and political beliefs, peaked on a day that could determine whether the Democrats’ 2020 nomination fight will stretch all the way to the party’s July convention or be decided much sooner.
Yet with voting under way across 14 states and one US territory, the political world was bracing for a long night almost certain to provide new drama.
The crown jewel of Super Tuesday, California, continues voting until 11pm (eastern US time), with final results not expected until early Wednesday or even later.
The day was also testing the strength of another Democratic heavyweight, New York billionaire Mike Bloomberg, who was appearing on a presidential ballot for the first time after skipping all four contests last month.
Today is our first step to making Donald Trump a one-term president.— Mike Bloomberg (@MikeBloomberg) March 3, 2020
I'm running to bring integrity and competency back to the White House. But I can't do it alone. We need you to vote â and we need your friends to vote â and your friends' friends to vote! #SuperTuesday pic.twitter.com/s4PJnTeaaA
Mr Bloomberg banked on more than half a billion dollars in advertising and ground operations in an unorthodox and untested strategy that relied on Mr Biden’s perceived weaknesses earlier in the year.
Mr Bloomberg and Massachusetts Sen Elizabeth Warren loomed as potential spoilers as the candidates jockeyed to cross the voting threshold to secure delegates, a move that could prolong the nominating battle.
Whether you live in Maine or California â or any Super Tuesday state in between â Iâm asking for your vote today. Together, we can beat Donald Trump and set our nation on a new path.— Joe Biden (@JoeBiden) March 3, 2020
Head to https://t.co/Hy8C4n0lUk to confirm your polling location and get out and vote! pic.twitter.com/nR6yukLMRy
The Democratic race has shifted dramatically over the past three days as Mr Biden capitalised on his commanding South Carolina victory to persuade anxious establishment allies to rally behind his campaign.
Amy Klobuchar and Pete Buttigieg abruptly ended their campaigns and endorsed Mr Biden, though their late departures meant their names will still appear on ballots.