WASHINGTON (AFP) - Tuesday's (March 1) votes in a dozen US states have cleared the air in some respects, and muddied the waters in others.
The Super Tuesday contests showed Hillary Clinton reclaiming her mojo against Bernie Sanders. It was a big night for Donald Trump, too, but what will the establishment do about it?
Here are four lessons learnt from the events of Super Tuesday.
1. TRUMP THE 'INEVITABLE' CHOICE FOR REPUBLICANS
The billionaire businessman at the centre of the Republican race cleaned up on Tuesday (March 1) night, winning at least seven of the 11 states at stake.
"It's awfully close to inevitable" for Mr Trump to win the nomination, said Professor Dante Scala at the University of New Hampshire.
About 30 per cent of the Republican delegates, the men and women who choose the nominee at the conventions, have been awarded so far through a proportional system, with Mr Trump in the clear lead.
After March 15, most state races are winner-take-all. By the end of the month, 62 per cent of delegates will have been awarded.
The longer the race goes, the more difficult it will be to oust Mr Trump. If he obtains 1,237 out of the total 2,472 delegates, he clinches the nomination.
2. TOO LITTLE, TOO LATE FOR CRUZ AND RUBIO
Meanwhile his two main competitors, Senators Ted Cruz and Marco Rubio, are duking it out for the role of Trump spoiler.
Republican leaders may have thrown their weight behind Senator Marco Rubio as the antidote to Mr Trump, but Tuesday's (March 1) results confirmed what millions of voters felt in their gut: It was too little, too late.
After spending the past week brutally attacking Mr Trump, scooping up major endorsements, and presenting his case as the mainstream candidate, Mr Rubio finished a disappointing third place on the night, behind Mr Trump and Mr Cruz.
Many have laid the debacle at the foot of the Grand Old Party.
"The party itself, faced with the real prospect of Donald Trump being the nominee, failed to act to stop him before he got off the ground," Prof Scala said.
Mr Rubio has vowed to go on, and is now staking his candidacy on winning his home state of Florida on March 15, even though Mr Trump is leading in polls there.
"Winning Florida is a necessity for him," Mr Kyle Kondik, managing editor of Sabato's Crystal Ball at the University of Virginia, said of Mr Rubio.
3. CRUNCH TIME FOR THE GOP
The Republican Party has been scrambling to prevent a Trump nomination, but nothing has worked. Now it's crunch time.
Some Republicans, notably Senator Ben Sasse, have suggested either a third party or independent run against Mr Trump. Others point to party operatives potentially altering the rules of the convention in order to prevent a Trump takeover.
"There's a danger here. If Republicans go after him, they're destroying their own nomination," strategist Frank Luntz told CBS. "If you try to kill him, you may be trying to kill your own flesh and blood."
With Mr Rubio faltering, former candidate Lindsey Graham, an establishment US senator who detests Mr Trump, points to a last resort.
"We may be in a position where we have to rally around Ted Cruz as the only way to stop Trump," Mr Graham told CBS.
4. MOMENTUM ON CLINTON'S SIDE
"By the end of tonight, we are going to win many hundreds of delegates," Senator Bernie Sanders told his supporters, noting there were still another 35 states to vote after Super Tuesday.
Even though he won four states on Tuesday, the message from Mr Sanders, who has based his campaign on ending economic inequality, fell flat among a crucial Democratic bloc: minority voters.
More than 80 per cent of African-Americans voted for Mrs Clinton in southern states, exit polls showed. And in Texas, two-thirds of Hispanic Democrats voted for her.
Mrs Clinton also won handily among women, who represent more than half of the Democratic electorate. Altogether, she has won 11 of the 16 primary races to date and holds a substantial delegate lead.
Mr Sanders stunned the establishment last year when he pulled ahead of Mrs Clinton in some states and drew huge crowds to his rallies. But his path has narrowed dramatically, and momentum is now on Mrs Clinton's side.
