The whole scandal around John McCain's lobbyist Vicki Iseman reminds me that candidates have an uncomfortable relationship with lobbyists. McCain, who initially billed himself as a man of integrity, even slapping his name on the updated campaign finance reform (which he is currently trying to untangle himself from). Clinton herself defended her decision to accept lobbyists' money early in the campaign, earning herself a lot of attacks from the left. Obama made a pledge not to accept lobbyists' money, but even that isn't a gold-plated promise.
The thing is, lobbyist sounds really bad. What we think of are massive corporations and slick K Street lawyers trading lavish dinners for some serious earmarks. And that is a good chunk of what goes on. But lobbying is also grassroots people talking to their legislators and even paid lobbyists from places like Greenpeace and student coalitions. To dispel lobbyists from campaigns is a little like saying that candidates aren't going to use money or try to get votes in their campaigns. Because modern campaigns rely so much on money and media coverage, eliminating lobbyists from the picture is virtually impossible unless we're willing to switch over to a totally publicly funded campaign system. And no one wants to do that because no one wants to lose.
There's no doubt that McCain is in trouble now, because he billed himself as above dirty money. Maybe Clinton had it right, maybe you should just accept that at some point, as a presidential candidate, you are going to accept money from large corporations. At least then you won't be a hypocrite.