Results are now in for the first primary: Cruz for the Republicans, Clinton for the Democrats.

What does this mean for the US presidential election 2016?

For Republicans the Iowa result opens a can of worms. As I've argued previously, a Trump win in Iowa would have effectively ended the race. Very likely Trump would have gone on to win every state. For this reason Trump really wanted a victory in Iowa, but he didn’t expressly need one to remain the GOP frontrunner. Now we’re in for a protracted primary season.

There isn’t really a winner from Iowa on the Republican side. Ted Cruz needed to come first and he did. Yet it remains hard to see Cruz leveraging this victory to build significant momentum elsewhere. Cruz appears to be doing well until one considers that his campaign strategy depends on Trump leaving the race and inheriting his supporters. With Trump still the frontrunner, Cruz is very unlikely to win the nomination.

Marco Rubio did far better than expected, very nearly knocking Trump down to third. If Rubio had managed to finish second, it would've upended the whole primary race. As is, Rubio still has a major problem. The New Hampshire vote is far more fragmented among the establishment candidates, and Trump’s lead there is very substantial. Moreover, Cruz might have just enough momentum from Iowa to come in second in New Hampshire; and a third place finish there for Rubio won't be good enough.

Trump lost an opportunity to wrap up the nomination early, yet by winning second place he achieves his main objective. Accordingly, Trump is still likely to win the nomination. Despite the hype, the only chance for Rubio is to beat Trump in New Hampshire, and that is a remote possibility at best.

The Democrats

Sanders has been surging. As Emma Connors points out, he pulls massive crowds, brings vast numbers of young people into the political process, competes with the GOP frontrunner for votes, and has shown himself capable of raising vast sums with grassroots campaigning, with average donations of just $US27 each.

And yet coming into the Iowa caucus Hillary Clinton has uniformly remained the Democrat frontrunner – why?

South Carolina.

South Carolina will be the fourth state to caucus (after Iowa, New Hampshire and Nevada), three days prior to the 1 March ‘Super Tuesday’ primary votes. South Carolina is Clinton’s fortress. She’s invested strongly to build a solid ground game in a state where polling has her ahead of Sanders 2-to-1.

Sanders had hoped to deliver a major upset in Iowa but Clinton held on, albeit by the slimmest of margins. There is no denying the momentum is now with Sanders and this catapults him into serious primary contention. Assuming his strong showing in Iowa is followed by a convincing victory in New Hampshire, this double-barrelled momentum might just give Sanders enough political velocity to punch through Clinton’s South Carolina walls. Nevertheless, the odds remain against Sanders.

The bottom line

For Republicans, a Cruz win in Iowa was essential for any candidate not named Trump, and Rubio’s impressive showing guarantees a drawn out primary race. But, despite the Rubio surprise, the Iowa result aligns closely with expectations, solidifying Trump’s position as the GOP frontrunner and likely nominee.

On the Democrat side, Clinton’s aura of inevitability was punctured but she held her position. The closeness of the Iowa race suggests it is by no means over for Sanders, and he will enjoy a honeymoon in media coverage. Yet Sanders must now achieve a truly dominating victory in New Hampshire if he’s to be competitive in South Carolina. Clinton is still the frontrunner.

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