There are the obvious financial motivations for why the Conservative Party and David Cameron find themselves in such trouble over their donors and what they get for their money. As party memberships decrease, donations have become ever more important to fill the funding gap.

But why are hugely successful businessmen so desperate to have private audiences with top-ranking politicians? Speaking to a Conservative PPS in the House of Commons yesterday afternoon, he was bemused that they saw all this effort as worth their time compared to concentrating on building their fortunes.

I’ve got one idea. It’s not only about getting maximum bang for their buck when they donate to the Conservatives. Believe it or not, politicians are still sexy. I’ve witnessed businessmen, who five seconds earlier have been aggressively criticising government policy, turn doe-eyed when the actual politician responsible talks to them. Be it the power, the elected office, the Georgian rooms of No 10 Downing Street - there remains a glamour about politics that you don’t get as the chairman or chief executive of a FTSE 100 company. And have you ever met a City type who declines the opportunity to discuss politics?

Chequers is a lovely house – but so are most of the abodes visited by this level of businessman. They love hanging out with politicians as much as the other way round. That is why you will continue to find parties offering personal contact as the cherry on the cake of a “premier league” donation.

Companies could simply make their views made very clear to the relevant department. Hanging out with the PM is about more than politely accepting an invitation. It makes the potential donor giddy with excitement. And while there remain no changes to how our political parties are funded, and that seems an impossibility after yesterday afternoon’s unbelievably bad-tempered exchanges in the Commons, then you will see cash for contact remaining an offering for party donors.

Tags: Cash for access, David Cameron, Party funding, Peter cruddas