[yummyfajitas]

In practice, SuperPAC donors just tell the legislator why the check was written, or in which case it will be.

If it were not a check, but merely using influence, would things be better? I.e., if Krugman were to offer to endorse Romney only on the condition that Romney expands Obama/Romneycare, would that be acceptable?

Or how about if some rich person stated he would buy a newspaper and use the newspaper to push Romney?