BBC News - Thursday's Eastleigh by-election: A few thoughts 26 February 2013 Last updated at 19:43 Most MPs I have spoken to - of all political colours - believe the Rennard affair will have only a marginal impact on the result. They say that if the electors of Eastleigh do not seem to care about Chris Huhne's behaviour, they will probably not care about the allegations against Chris Rennard and the Lib Dem's handling of the crisis. The by-election will above all be a test of the respective party machines. When do the parties sense that voters have reached saturation point and stop bombarding them with calls, visits and leaflets? How good is their data about electors' likes and loves and voting intentions? How well do they organise and get their supporters out on the day? The Lib Dems are totally bedded in. One Tory MP who knows the patch very well told me that the Lib Dems not only hold all the council seats in the constituency, they also hold all the parish councils. Chris Rennard - to pluck a name from nowhere - whipped the party into shape for the 1994 by-election and council elections and they have dug in hard ever since. The Conservatives will take the flak for being in government. Many MPs say voters in Eastleigh do not seem to view the Lib Dems as a party of government. So, for example, they say middle class concerns about the loss of the AAA credit rating are being directed at the Conservatives and not their coalition partners. Conservative MPs give a mixed impression of their party's organisation on the ground. Some MPs and ministers I have spoken to say their party machine is better than is usual in by-elections. They talk of turning up and being given their marching orders quickly instead of being waiting around until someone can find them a few streets to knock up. But other Tory MPs talk of poor canvas returns and of a confused chain of command. Who is in charge, they ask? Is it Stephen Gilbert, the prime minister's political secretary, or is it Darren Mott, the Tories' deputy director for elections? They also point to an aged local party that is in dire need of renewal. For example, the Tory group leader on Eastleigh borough council, Godfrey Olson, is well into his 80s and has held the same seat since 1955. Whatever the result, MPs belonging to the losing party will infer too much from the defeat. This is particularly true of Conservative MPs. They say that if the party loses, David Cameron will come under instant pressure to move to the right/legislate for an EU referendum/slash taxes/ditch George Osborne and so on. If UKIP does well and Tories can claim that the loss of votes to UKIP cost the Conservatives the seat, this pressure will be even greater. In other words, what matters on Friday is how the parties react to the result. This by-election will not predict the result of the next general election; it will not tell us that the Lib Dems will hold or lose every marginal seat against the Tories; it will not tell us how Labour will do elsewhere in the south of England. But the reaction on Friday will provide a snapshot of the morale of the losing party. Do they panic? Whose head do they demand? What policy response do they call for? And the resulting debate will have a further impact on that morale. Both Lib Dem and Tory MPs claim the Labour vote is being squeezed. Several Lib Dems I spoke to said they were surprised by how poorly the Labour vote seemed to be holding up. They claimed they were picking up much of it. That remains to be seen. Either way, Labour explicitly made this election a test of their one nation appeal and they will be probably be judged by it. All sides expect UKIP to do better than initially thought. They say the anti-politics mood is thriving in Eastleigh where many voters appear hostile to politicians, they are worried about immigration, they feel ignored and taken for granted by Westminster, and, frankly, they are fed up with people stuffing paper through their letter boxes and asking the same question over and over again. All this is grist to UKIP's mill.