Ahead of the busiest, and invariably decisive spell of primary season, the importance of Tuesday's Democrat debate from South Carolina cannot be overstated. Following his resounding, poll-beating victory in Nevada, Bernie Sanders is even money favourite to win the nomination.
This won't be the final debate but may very well be the last chance for his rivals to stop him. Expect the gloves to come off. The fact such generous odds are available may reflect the fact punters anticipate a bloodbath.
The last two debates have proved these high-exposure, set-piece events can have a significant impact. After New Hampshire, debate winner Amy Klobuchar stormed past polling expectations into third place. A poor follow-up in Vegas then stopped the 'Klobucharge' in its tracks. On the same stage, a concerted take down of Michael Bloomberg may have killed the billionaire's hopes.
Attacks on Sanders bound to take centre stage
Whilst his rivals will doubtless repeatedly accuse Bloomberg of trying to buy the presidency, there will be less focus on him. The billionaire's debut meant Sanders was able to escape the worst headlines after Vegas. Criticism of his spending plans and associated risk to the Democrat ticket failed to cut through. Those attacks will be relentless tonight.
In an interesting development, Bloomberg is throwing the kitchen sink at Sanders. Whether it helps him is questionable, but these negative ads do have the potential to hurt the front-runner.
The independent socialist Senator escaped deep scrutiny of his positions, and his past, in 2016. Many Democrats understandably fear the damage, once Republicans bombard voters with footage of him praising Fidel Castro, the Sandanistas and even the Soviet Union. Or stuff like this, bound to alienate large swathes of natural Democrat voters.
Bloomberg, for his part, will doubtless go after Sanders' record on guns, while emphasising his own progressive credentials on gun control. See these tweets from his chief surrogate.
Whilst I doubt this will make Bloomberg any more electable to a left-wing audience, I do believe he can hurt Sanders badly in forthcoming races. African American voters make up a very large chunk of the Democrat primary audience in Southern states. Although polling competitively, his share is in the low twenties and vulnerable to any candidate who can unite the black vote.
Can any rival unite the black vote?
Joe Biden, benefiting from his proximity to Obama, started way ahead among black Democrats. His dire campaign, however, resulted in many drifting off to rivals. Tom Steyer, for instance, has directly targeted SC black voters, via ads to their media and promises of huge reparations for slavery. Bloomberg is also heavily targeting this influential segment.
A higher percentage of black voters are currently undecided than the white vote. Their choices will be pivotal but, at this stage, Biden remains in pole position for Saturday's primary. Polls range from a 15% Biden lead to a tie and the former VP has resumed favouritism at 1.75/7.
Biden set to win prized endorsement
So long as Biden performs respectably tonight (granted, no certainty), I expect he will receive the hotly anticipated endorsement of Representative James Clyburn - the most influential black Democrat in SC. Clyburn is close to Speaker Nancy Pelosi, so it would be an enormous shock were he to back Sanders, and hugely divisive if he backed Bloomberg or Steyer.
Indeed this is a huge, all-or-nothing night for Biden. His campaign has been a disaster and status as national leader long gone. Yet a solid performance would put him in a strong position ahead of Super Tuesday, where various good targets in the South are up for grabs.
If, and it is a huge if, the 'moderates' are to stop Sanders, they need to unite quickly. I've never believed they should coalesce around Biden but it looks like they will. Pete Buttigieg and Klobuchar lack the support among black voters and ability to amplify their campaign in these Southern states. Bloomberg is simply a poor fit for the Democrats.
SC victory could see Biden unite moderate lane
It seems near-certain that, after Super Tuesday, Sanders will hold a big lead and Biden will be in second, having accumulated plenty in the South. If so, the others will have to decide whether to carry on in vein or realign behind Biden. With that scenario in mind, I placed my first bet on Biden of this entire campaign last night. I don't expect it to win but the odds should shorten up considerably.
And what of last week's star debate performer, Elizabeth Warren? That took place too late to affect her Nevada performance but it did improve her national polls. There remains a very narrow pathway. She needs to improve enough to hit 15% in most states, accumulate delegates and perhaps pull off a win in a big state.
That would be enough to stay in, and thus potentially set up a three-way race with Sanders/Biden, in which she would be the 'unity candidate'. A supporter of Sanders' flagship progressive policies on healthcare and education, without any of his toxic baggage.
A Warren revival is a longshot, as reflected by the odds. Nevertheless last week's performance offered much hope that she can take down Trump on the debate stage. Expect her useful billionaire foe Bloomberg to be on the receiving end of another barrage tonight.
Follow Paul on Twitter and check out his website, Political Gambler.