Editor's note, 7.30pm: Since TheWeek.co.uk broke the news that Patrick Mercer had been suspended from Parliament for six months, the MP has resigned his seat, triggering a by-election in his Newark constituency in Nottinghamshire.
THE WEEK has learned that one of David Cameron's worst enemies in the House of Commons, Patrick Mercer, the MP for Newark, was today banned from Parliament for six months as a result of revelations published last year that he took cash in return for tabling questions in the Commons.
Which raises the critical question: will the former Tory, who now sits as an Independent, stand down as MP and force an extremely awkward by-election?
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The Sunday Times reported two days ago that Mercer had told friends that if he was banned for as long as six months he would resign.
If he sticks to his guns and makes that announcement in the coming hours, the Conservatives will face a tricky choice as to when to call the by-election.
If it takes place in four or five weeks' time – which would be normal – then the Tories will find themselves defending a seat against what is expected to be a buoyant Ukip party who will have just come out of a famous victory – if the pollsters are right - in the European elections on 22 May.
Tory spin-doctors will be busy briefing that the EU elections are a special case and that they have little bearing on Westminster consituency politics. But a super-cocky Nigel Farage could make that a difficult argument to spin if an actual by-belection gives Ukip the chance to test its strength.
The Tories' other choice is to call the by-election immediately – assuming Mercer carries through with his promise to stand down – and hold it on 22 May, the same day as the EU and local elections. That might give them the best chance of victory, with Ukip occupied elsewhere.
Whether Mercer stands down is a moot point: one Westminster wag told me this afternoon that Mercer will simply do whatever annoys David Cameron the most.
Mercer is a former Army officer who was covertly filmed last year - in a joint operation by the Daily Telegraph and Panorama - agreeing to set up an All Party Parliamentary Group at the request of reporters posing as lobbyists seeking to get Fiji's supension by the Commonwealth lifted.
Mercer also offered to produce a Parliamentary report on behalf of a client in return for £4,000 and the promise of further income.
Today's ruling that he be banned for six months was made by the House of Commons Standards Committee.
Mercer is probably more famous in the halls of Westminster for the extraordinary comments he made about his party leader in 2011 when he was secretly recorded describing Cameron as an “arse” and the worst prime minister since William Gladstone.
Cameron, one might assume, would therefore be very happy never to see the man again and to learn that he has decided to disappear from Westminster
But there is no doubt a by-election in May or June is the last thing Cameron needs.
If the recent YouGov poll for the Sunday Times is anywhere near accurate, the upcoming EU elections will be the first time any party other than Labour or the Conservatives has topped a national poll since before the First World War.
YouGov puts Ukip in the lead on 31 per cent ahead of second on 28 per cent with the Tories at 21 per cent. The Liberal Democrats are a distant fourth and face a wipeout.
On the face of it – and if there were no other elections in the offing - the Tories should win Newark at a canter. Mercer took more than 50 per cent of the vote in 2010 and had a majority over Labour of more than 16,000. But Mike Smithson of PoliticalBetting predicts that the contest could become “a fierce three party battle”.
He notes that the Tories have a terrible record of defending by-elections when in government. The last time they did so successfully was in 1988 when William Hague was elected.
Smithson says that with Farage's party surging and threatening a breakthrough on 22 May, the Nottinghamshire constituency of Newark could be the "ideal platform" for Ukip to win "the prize that has so far eluded them – a Westminster seat". He says Labour would also compete hard and would have more than 10,000 2010 Lib Dem voters to squeeze.
