There are few sights in politics less edifying than the House of Commons roused into a state of confected fury. (Actually, it is the sound more than the sight that is off-putting -- the braying roar of hundreds of MPs hurling theatrical fury at one another does not obviously signal constructive debate.) Parliament was at its noisy, shouty worst for yesterday's statement by Cabinet Office Minister Francis Maude on the "cash for access" scandal. In fairness, Maude himself started off pretty sedate, while Labour MPs went berserk. Ed Miliband was fairly even-tempered too but by then berserk was established as the backbench theme of the occasion and the Tories embraced it.
The arguments were predictable. Miliband insisted that the issue in question was David Cameron's judgement and demanded an independent public inquiry into the specific allegations that high-rolling donors have secured intimate soirees in Downing Street with their lavish contributions to party coffers. Maude hit back with scattergun blasts at Labour's failure in office to reform party funding and its current dependence on trade unions. This is pretty much how the argument will proceed from now on. Miliband wants to keep the focus as narrow as possible, ideally so some mud sticks to the Prime Minister; the Tories want to widen it out as quickly and as far as possible so the whole scandal is seen as somehow intrinsic to politics in general with no one party better or worse than the others.
Ultimately, I suspect the Tories will win this particular tug-of-war for two reasons.
First, much though Labour would like people to connect the current scandal to Tory sleaze of bygone days - the mid-Nineties, cash-for-questions etc. - the public are just as likely to recall Labour sleaze - cash for honours - which is more recent. As with the expenses scandal, the default judgement will be that "they're all the same".
Second, the Liberal Democrats will pull hard in the direction of generalising the issue rather than keeping the focus specifically on Cameron and Tory donors. Although the junior coalition party has an interest in keeping the Conservative brand toxic (so as to appear all the more vital as a moderating influence) , the real prize for Clegg and friends from all of this is serious progress on funding reform. The junior coalition party is broke and does not have a safety net of reliable donors in the way that the Tories can tap up their pet tycoons and Labour can fall back on the unions. Levelling the playing field is a matter of financial survival for the Lib Dems.
Also, crucially, although the left-leaning wing of the Lib Dems might be more appalled by the idea of fat cats wining and dining the Camerons, the party's MPs are much more focused on union money. At the last election, it was trade union war chests that funded a lot of vicious trench warfare in Labour-Lib Dem contests. That power is felt at least as keenly as the money that Lord Aschcroft feeds into Conservative target marginals, if not more so. The Lib Dems will gladly encourage the idea of equivalence between rich Tory financiers and the unions because, when it comes to being outspent in campaigns on the ground, there is ample resentment to go around.