By-election win: Could UKIP be kingmakers after general election?

Nigel Farage has predicted UKIP could hold the balance of power following the next general election after his party gained its first elected MP.

The UKIP leader said his party had momentum after Douglas Carswell won the Clacton by-election by 12,404 votes.

However, history suggests that although smaller parties can make a big impact at by-elections, translating that into wider political success is far from easy.

Nick Robinson reports.