By-elections are notoriously hard to call. But everyone who comes back from Eastleigh says the same thing, UKIP are the party with forward momentum. This morning’s Populus poll bears that out. They are in third place with 21 per cent, with the Tories second on 28 and the Lib Dems ahead with 33. But, as the indispensable UK Polling Report points out, if you don’t reallocate some of the undecides to the party they voted for last time, UKIP are doing even better. The numbers then are UKIP 25%, Tories 26% and Lib Dems 31%.

As I said in the magazine this week, UKIP are picking up support from all three parties. Things could get very interesting there if more Labour voters shift to UKIP as the best anti-coalition vote.

For Labour, coming fourth in Eastleigh would be an embarrassment. (Just read Tristram Hunt’s piece in this week’s Spectator to see why). It is hard to claim to be a one nation party when you’re struggling to compete in the south, and Eastleigh is hardly the strockbroker belt.

A strong UKIP showing will cause problems for David Cameron too. For it will increase calls from his own benches for more UKIP-style policies.

Tags: Coalition, Conservatives, David Cameron, Eastleigh, Elections, Labour, Liberal Democrats, UK politics, UKIP