Democrats, from the top politicians on down to their messaging drones at Think Progress, have targeted the Koch brothers, as documented here many times.

So good for Koch Industries for sending this letter to Sen. Patty Murray in response to a “request” for a sizable donation to the Democratic Senatorial Campaign Committee (h/t Ben Smith):

Dear Senator Murray:

For many months now, your colleagues in the Democratic Senatorial Campaign Committee leadership have engaged in a series of disparagements and ad hominem attacks about us, apparently as part of a concerted political and fundraising strategy. Just recently, Senator Reid wrote in a DSCC fundraising letter that Republicans are trying to “force through their extreme agenda faster than you can say ‘Koch Brothers.’”

So you can imagine my chagrin when I got a letter from you on June 17 asking us to make five-figure contributions to the DSCC. You followed that up with a voicemail* indicating that, if we contributed heavily enough, we would garner an invitation to join you and other Democratic leaders at a retreat in Kiawah Island this September.

I’m hoping you can help me understand the intent of your request because it’s hard not to conclude that DSCC politics have become so cynical that you actually expect people whom you routinely denounce to give DSCC money.

It is troubling that private citizens taking part in the discourse have become the targets of White House and DSCC fundraising missives, and we would certainly encourage you to rethink that approach. Ultimately, I expect voters will see through that and will weigh the issues on the merits alone. But in the meantime, if you could provide me some insight on what exactly you are asking of us and why, I would be most grateful.

*Here is the voice message Murray left in connection with seeking the donation.