The status quo wins

Thursday's 10-way clash in Houston was a debate without knock-out blows. Joe Biden pinned down the progressives on costs, he in turn was challenged over his conservatism.

There were neat sound-bites, searing attacks on Donald Trump and some genuinely moving moments at the end as candidates were asked to name setbacks they had overcome. But fundamentally it did not feel like there was a game-changing moment.

And that benefits the front-runners. This race is still in its infancy, with five months to go before the first votes are cast in Iowa and another five after that before a winner is crowned.

Even so, every debate when Joe Biden, still leading by a mile according to polling, is not politically damaged is an opportunity missed by his rivals. His double-digit lead has remained intact all year - in fact for the last three years.

If there is to be a sudden moment when his lead is wiped out, it did not come here.