Iowa caucuses: An unpredictable night may offer a sign of things to come

Ted Cruz was close to tears. He hugged his parents and his wife. For a man known for his relentless ambition, and his effortless ability to make enemies, this was a remarkable victory.

The Texas Senator is widely disliked in Washington - even despised by his colleagues in Congress - for his arrogance.

And yet his political skills are not in doubt and they brought him the sweetest of victories here. But it's far from clear this is the man to unite a fractured party.

Cruz is angry. And he needs voters to be too. He is the hand-grenade candidate.

Cruz will have almost no time to savour victory. He now needs to persuade Republicans the Trump phenomenon is receding - and then turn his attention to halting the rise of Marco Rubio.

For the young Florida senator far exceeded expectations, and may emerge as the establishment choice.

Donald Trump - who was widely expected to win - had to display a quality few thought he possessed: humility.

He now must do well in New Hampshire to avoid the "loser" tag he loves to give to others.

Clinton v Sanders: A remarkable battle

At the same time an extraordinary battle was playing out on the other side. As we witnessed during the Caucauses, Democratic Party voters are deeply divided - torn between the populism of Bernie Sanders and the appeal of Hillary Clinton.

This was essentially a dead heat. And for a self-described democratic socialist like Sanders to run so competitively with Hillary is a sign of the depth of the frustration with Washington politics.

Iowa played its role in narrowing the field. Now for both parties the gruelling contest can begin in earnest.