Define letting? The political system has de-criminalized vote buying by re-branding the bribers as 'lobbyists' and protecting it as a 1st Amendment right. Even Guilfoyle's controversy was asking for 100k to her Amex account from a "lobbyist". In most countries it's a jailable offense.
This lobbying means that the politicians might be elected by "us" but they work for "them" - the "lobbyists."
Does this answer your question sufficiently?