Why do politicians change parties?
Reports of Conservative voters jumping ship to join UKIP follow a long tradition of political defections including Winston Churchill and the SDP which was formed mainly from the Labour ranks in 1981.
Jo Coburn spoke to Conservative MEP Sajjad Karim, who used to be a Lib Dem, but traced his political activities back to Tory circles when he was seven.
Ex-Tory councillor Suzanne Evans, who has just switched to UKIP, said she felt her residents were not being properly represented by her old party and ended up delivering leaflets that were "wishy-washy" and "Labour light".
And Lord Adonis spoke about his political travels, via the SDP and Liberal Democrats, before settling on Labour, where he was in Gordon Brown's cabinet.
Winston Churchill pictures are from Pathe News.
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- From the section UK Politics