Democrats threaten donors with retaliation if they give money to Republicans

This seems like a pretty good reason why donors should be anonymous. From Politico:

Democrats on K Street are warning their corporate clients: Give to Republican challengers in the 2012 election, and you’ll regret it come tax reform time.
Lobbyists are getting that message from allies of powerful Democrats such as Senate Finance Chairman Max Baucus (D-Mont.), who is closely watching support for Rep. Denny Rehberg, a Republican challenging Sen. Jon Tester (D-Mont.). Baucus supporters fear that if Rehberg ousts Tester, Baucus could be next to face a serious Republican challenge in the state.
One K-Streeter close to the Baucus operation said the senator considers a gift to Rehberg a contribution against him. Another Democratic lobbyist told a client to take his name off a Rehberg fundraising event because it would be hurtful to his company, according to sources.
The case K-Streeters are making to their clients: It will be a hard sell next year to get Baucus’s support on business-friendly tax perks set to expire or the Bush-era tax cuts that must get through his committee.
The game of hardball is a bold example of a powerful chairman willing to leverage his power to protect his party’s majority, his home-state colleague and potentially his own seat.
“We all know how this particular game is played: A chairman of a committee has his allies downtown quietly put out the word that folks with business before that committee may want to think twice about contributing to a candidate opposing one favored by the chairman,” said a Democratic oil industry executive. “Getting the message out this way provides deniability to the chairman yet ensures that everyone in the lobbying community gets the joke.” . . .