Nigel Farage has repeated his promise/threat to stand down as leader of Ukip if his party fails to win any seats the election. He made the remarks on being confirmed as Ukip’s candidate for Thanet South, where he is hoping to overturn a Conservative majority of 7,617.

Farage’s vow could mean that by this time next year three of the four main parties will be in the middle of choosing new leaders. Farage, Clegg and Cameron/Miliband may all resign or be voted out within months of the election, depending on the scale of their respective party’s losses. Only the person who becomes prime minister will be safe.

Meantime Sky News has been reporting details of 12 seats on Ukip’s “target list”. Some of them are not a surprise – indeed, the polling Sky has used to draw up the list has been in the public domain for a while. It’s not an official list so it’s misleading to treat Sky’s report as fact. There are also some odd choices, which Mark Wallace on the ConservativeHome website puts down to Ukip using local and European election results as a “massive opinion poll to choose their target seats”.

For example, there are nine Tory seats on the “list”, but only two are marginals:

Those are some very safe Tory constituencies. About the only thing most of them have in common is that they are near the seaside.

I’ve mentioned before my puzzlement at Nigel Farage’s decision not to stand in a Tory marginal or Labour target, where he could potentially cause a lot of disruption. This list, such as it is, seems to be informed by a similar mindset. It’s as if someone has ignored the parliamentary arithmetic in these constituencies and instead cherry-picked some favourable statistics from which to extrapolate some headling-grabbing aspirations.

I’m also puzzled why there is only one Labour seat on the list: Great Grimsby. I’m sure Ukip will want to be seen to be threatening all the main parties, not just the Conservatives.

Completing the list of 12 are two Liberal Democrat seats: Eastleigh, where Ukip came second in the by-election of 2013, and Portsmouth South, currently held by the Lib Dem-turned-independent Mike Hancock.

Both have a very strong local Lib Dem following that has stayed loyal despite the behaviour of past and present MPs. The implication here is that Ukip will be hoping to profit from those antics.

If and when Ukip does publish its official list of targets, I imagine there will be some overlap with this one. I really can’t see the party throwing “the kitchen sink” at the likes of David Lidington in Aylesbury, however, who has held the seat comfortably since 1992. Nor for that matter Sir Roger Gale in Thanet North, who has been there since 1983.