What the Thune bloggers did was media intimidation. We have the identical problem with the national media. The problem with the media is too little access for alternative media, not too much access. I don't know how you pass legislation to give the media a spine or improve their journalistic skills. Maybe they could be required to read the Daily Howler before they start work every morning. Bob is on a roll with Sen. Hagel and our clueless media on Social Security lately.
I recall when Bush first suggested privatization, Bob Somerby predicted the media would do their usual feckless job. He was right.
The answer is not more government regulation. The answer is more freedom and a more robust response from the campaign and the media. I don't know how you fix our intert media, but restrictive legislation is not the solution.
maybe you could just demand full disclosure. Any blogger that was paid by any political organization (campaign, 527, or any other advocacy group registered as such in the tax code) must have that affiliation displayed prominently on the front page for 2 years, and then kept in an archive linked from the front page ad infinitum.
Journalists wouldn't be intimidated by a blogger, who they knew was a campaign surrogate. It doesn't hurt the blogger at all, if they engage in real blogging. It would even give the blog legitimacy with readers.