Today's daily YouGov tracker for the Sun has topline voting intentions of Conservative 36%, Labour 42%, Liberal Democrats 9% and others on 14%. This is the highest collective level of support YouGov has recorded for the minor parties since the election. One of our daily polls earlier this week also showed 'others' with 13%, so this appears to be more than just freak result.
The largest part of this support is going to the United Kingdom Independence Party (UKIP, pictured), currently on 6%. Some of this may be down to the Barnsley effect - a knock on from the publicity UKIP recieved after coming second in the Barnsley Central by-election. However, the slow upwards trend in support for other parties has been apparent since long before the Barnsley by-election, so it is just as likely that minor parties are benefiting as alternate recipients of protest votes from those unhappy with the current government, but who don't wish to support Labour.