Ukip’s percentage vote in the Rotherham by-election last night – 21.8 per cent – was the highest Ukip has ever achieved in any parliamentary election. It was fuelled in part, no doubt, by the local row over the Ukip members who were foster parents, and had their children taken away by the local Rotherham council. This is the second time their candidate Jane Collins has come second in a by-election, having won 12.2 per cent of the vote in nearby Barnsley Central last year.

30 ukip r w After Rotherham, Ukip aims to top the 2014 Euro poll

Ukip also did pretty well too in the Middesbrough by-election yesterday, with 11.8 per cent of the vote, but less well in Croydon North where they got 5.7, though that was still more than the Lib Dems’ meagre 3.5 per cent.

The other notable feature of yesterday’s results was the BNP’s 8.46 per cent in Rotherham, just ahead of Respect, whose candidate Yvonne Ridley did less well than I expected (especially given that her campaign was so much more visible than the BNP’s). Respect’s even more disappointing 2.9 per cent for Lee Jasper in Croydon North suggests George Galloway’s amazing 10,000+ majority in the Bradford West by-election last spring was a one-off, and that Respect is very much a one man band.

One should be careful about making too much of Ukip’s performance in Rotherham. As my former BBC colleague David Cowling says: “This was their best shot, given the adoption story and the deep divisions within the local Labour party over the selection of their candidate, and they played it hard.”

Ukip strategy is now quite clear – to replace the Liberal Democrats as the third party in British politics, having already replaced them as the natural party of protest. The two parties have been neck and neck in the polls for many months now. In five by-elections in the last two years – Barnsley Central, Corby and yesterday’s three results – they have come well ahead of the Liberal Democrats.

On the other hand Ukip were beaten by the Lib Dems in the seven other British by-elections which have taken place since 2010, including the contests two weeks ago in Manchester Central and in Cardiff South & Penarth. What we’ve yet to see is how they do in by-elections in solid Conservative seats, simply because, quite remarkably, we’ve yet to see a by-election in a safe Tory constituency in this Parliament.

The Lib Dems’ average vote yesterday was just under 6 per cent, compared with Ukip’s average of more than 13 per cent, though Ukip will need to do a lot, lot more to show they really have replaced the Liberal Democrats as the number three party. Ukip has very few councillors, right now, and no MPs. And it will find it exceedingly difficult to get an MP elected under the existing first-past-the-post system.

Their best bet is to persuade a popular, existing MP to defect and fight an election under Ukip colours. If a Tory MP was to defect and resign his or her seat to fight a by-election, it could be spectacular.

Ukip’s other aim is top the poll in the 2014 elections for the European parliament, having come second in 2009 (with 16.5 per cent of the vote). If they managed to come first in 2014, and continue to beat the Liberal Democrats in by-elections and in the polls then it would greatly strengthen Ukip’s case to be given a lot more TV coverage at the next Westminster general election in 2015. They’ll be arguing for a seat in any TV debates, and also for the broadcasters to given them automatic inclusion in all other election coverage. And if the broadcasters refuse, Ukip will no doubt take them to court.

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