Thanks in no small part to Donald Trump, the 2016 election campaign has become big news even earlier than usual. 11 candidates, (out of 16 left in the field) will debate in California tomorrow, suggesting the most open race in history.
The fundamental challenge facing 14 of them is simply being heard, in order to build the national name recognition required to compete with household names like Trump and longstanding favourite Jeb Bush. On current prices, this pair are taking out nearly 50% of the book.
At this very early stage, however, everyone is still in play. One good debate performance could transform a candidacy. One slip could destroy it.
See for example how, during the last two Republican contests, the following seven candidates either held early favouritism or got very close to it, only to either fail to reach the starting post or to be all but finished after the first two primaries.
Rudy Giuliani (2008)
The former New York Mayor became famous across the world with his eloquent response to 9/11, and regarded as an obvious future Presidential candidate. When the race to succeed George W Bush begun, he was the solid, clear favourite for over a year.
Remember, particularly during the early stages, these markets are predominantly played by British punters, and they may have struggled to understand the nuances of US politics. The party was in no mood to elect a social liberal like Giuliani and, once hostilities begun in earnest, he faded badly. After sixth place in Iowa and fourth in New Hampshire, his bid was dead in the water.
Fred Thompson (2008)
Former actor Thompson was another with the necessary name recognition and his more socially conservative profile looked the right fit. Around this time seven years ago, he was vying for favouritism with Giuliani and Mitt Romney. Again though, failures to even make the top-two in Iowa, New Hampshire and South Carolina put paid to his ambitions.
Mitt Romney (2008)
With his two main rivals stumbling, multi-millionaire Romney appeared to be the only one left with sufficient money and campaign resources to win a nationwide contest. Yet despite holding an enormous financial advantage over John McCain and Mike Huckabee, Romney came in only third after a dismal campaign.
Sarah Palin (2012)
From the moment McCain lost, his controversial running mate dominated international coverage and the market for 2012. Unlike McCain or his defeated rivals, Palin had tapped into a movement on the Republican Right that would soon become known as the Tea Party.
With her flair for publicity and massive name recognition, a bid for the main job seemed likely and was the subject of constant speculation. As it turned out, she never ran and backers had lost their money already at this stage four years ago.
Herman Cain (2012)
Probably the most bizarre frontline contender ever, for either nomination, Cain briefly vyed for favouritism at around this stage. The former CEO of Godfathers' Pizza's populist, anti-government rhetoric made waves with Tea Party types, in an early sign of the anti-politician mood that dominates their contest this time around.
A catastrophic interview on foreign policy, completely forgetting his lines about Libya, destroyed that brief momentum. A series of revelations about his private life finished him.
Rick Perry (2012)
The pressing concern for many Republicans at this stage was finding a viable alternative to Romney, who of course eventually won. Romney had never connected with the grassroots and strategists feared after 2008 that he was a poor, yet remarkably well-financed, candidate.
Texas Governor Perry perfectly fitted the bill and, once confirmed as a candidate in the race, swiftly assumed favouritism. Humiliation and a career-destroying moment awaited in the debates, however, as Perry forgot one of the three departments he was pledging to abolish. Oops!
Newt Gingrich (2012)
With desperation among Romney's opponents setting in, Gingrich now became their man. Nobody doubted the former Speaker's intellect or debating ability, but his reputation was damaged, both personally and professionally, from the 1990s.
True to form, Gingrich ran a fiery campaign, giving Romney both barrels and provided the Democrats with a stack of attack material on their eventual opponent. It didn't work and, apart from a win in South Carolina, the nomination never looked realistic.