From OMB Watch:
After the Federal Election Commission (FEC) formulated a rule on reporting campaign contributions bundled by lobbyists, many were concerned that it was too narrow and would not quite capture very much information. Now, we see those points were not misguided. The situations under which a member of Congress is legally required to disclose a lobbyist’s fundraising are limited. A recent analysis from the Associated Press found that only a few members of Congress are disclosing bundled contributions from lobbyists.