Do we know of any Labour defectors to UKIP other than Natasha Bolter, who doesn't exactly look like a prize catch (unless your name is Roger Bird of course lol)
As said, this poll says more about the level of intelligence of some voters, and is maybe not that surprising, nor necessarily a huge threat to Labour. People don't like to think of themselves as "extreme" in their voting intentions, as the following extract would bear out
"Fascinatingly, the Conservative Party is considered more right-wing by Conservative voters (7.11) than Ukip is by Ukip voters (6.28). Ukip voters see themselves as less right-wing (5.86) than Conservative voters see themselves (6.44)."
I think that is interesting, and telling, but maybe not so surprising.
And none of it appears to suggest people think UKIP is "left wing" as such", just not as right wing as the Tories. But then "right wing" has a stigma about it for many people, which is why this is maybe worse news for the Tories than Labour as a matter of fact.