In a mailing made public Monday, the Texas Republican's campaign added a defiant rebuttal to the letter, saying, "Democrats have made clear that their only agenda is the politics of personal destruction, and the criminalization of politics.
"They hate Ronald Reagan conservatives like DeLay and they hate that he is an effective leader who succeeds in passing the Republican agenda."
A spokesman for DeLay said the letter and accompanying multi-page rebuttal were sent last week to supporters and donors.
DeLay has been under siege in part because the House ethics committee admonished him last fall and in part because of questions raised in news reports about three overseas trips he took in recent years.
He has strenuously denied any wrongdoing and said he wants to appear before the chairman and senior Democrat on the ethics committee to clear himself.
The ethics controversy surrounding DeLay has spilled over to the panel itself. Democrats, accusing Republicans of pushing through a unilateral rules change to protect DeLay, have refused to allow the committee to conduct business.
While DeLay and others accuse Democrats of seeking political points from the controversy, some Republicans have privately begun to express concern that the party could be damaged unless a way is found out of the impasse.
In an overture to Democrats on the panel, Rep. Doc Hastings, R-Wash., the chairman, offered last week to change portions of the new rules. His proposal was swiftly rejected.
Republicans, speaking on condition of anonymity, have said they expect Hastings to make another attempt at compromise in the next several days.
A spokesman for DeLay confirmed the authenticity of the mailing to supporters after it was obtained independently.
In the mailing, DeLay wrote supporters that he was contacting them after receiving requests for a "fact versus fiction briefing document."
"It should come as no surprise that following the 2004 election-year attacks on the president that the Democrats, their syndicate of third-party organizations ... and the legion of Democrat-friendly press would turn their attention to trying to retake Congress," he wrote.
The accompanying summary said, "Tom DeLay does not stand accused of any violation of any law or rule in any forum and has never been found to have violated any law or rule by anyone."
In the case of a complaint that went to the ethics committee last year, the mailing said, three of four individual counts were dismissed and a fourth deferred.
"The committee sent him two letters containing informal warnings to be careful in the future for what it admitted were cases of first impression. The verb 'admonished' was used and is now exploited to mean some sort of sanction," it said.
Democrats highlighted this portion of DeLay's defense.
"He is still unwilling to admit that he did anything wrong," a spokeswoman for Rep. Nancy Pelosi, the Democratic House leader, told the new York Times.
As for three trips that have come under scrutiny, the mailing said journeys to Russia in 1997 and the United Kingdom in 2000 were proper.
It said DeLay went to South Korea in 2001 not realizing the organization that paid for the journey had registered as a foreign agent two days before the traveling party left the United States.
The mailing was the most recent attempt by DeLay to shore up his political support in the wake of ethics allegations.
Last week, he said the charges against him constituted the "Democrats agenda" and told reporters he didn't intend to answer questions about them. The same day, he granted a lengthy interview to The Washington Times, which is widely read among conservatives.