A majority of all defectors who voted Labour in 2010 but for a different party in 2015 said Ed Miliband had helped push them to another party. For those switching to the Tories, the second biggest reason was the fear that a Labour government would spend and borrow too much.

In the 1990s, the Lib Dems won a string of byelections at the expense of struggling Conservative governments. Christchurch, Ribble Valley and Eastbourne went straight back to the Tories at the next general election, but the Lib Dems held their later byelection gains - Eastleigh, Newbury and Romsey - in at least two subsequent general elections.

While loyalists and defectors overall said John Smith did a better job of standing up for Labour's values, they put Blair ahead on representing the whole country, appealing beyond traditional Labour voters and offering strong, competent leadership; switchers to the Tories gave him a clear lead in all categories.

Michael Ashcroft Quotes