Today is the day the UK Labour party picks it's next leader.
All signs point to Jeremy Corbyn, the sitting Leader, will be re-elected. Corbyn is popular with the left, and the Labour party has grown among the left in recent years. The party, at one time, had around 200,000 members. This was true during the Blair years. There is evidence that these people, who still support Labour, are strongly anti-Corbyn. However, they are outvoted by the 400,000 or so people who have joined the Labour Party in the past 18 months. While this brings Labour back to levels they saw in the past, it also means there is a real possibility that Labour could return to the sort of party they were under Michael Foot; a left-wing party that is unable to beat the governing Tories.
There isn't much more to say at this time. Perhaps if Corbyn somehow loses, I may do a further update, but all signs point to a healthy win with between 60% and 80% support.