The National Republican Congressional Committee has come up with some new ways and means to get the attention of potential contributors, but Democrats are howling that the campaign is misleading and unethical.

In a mass mailing last month under the signature of its chairman, Rep. Guy Vander Jagt (R-Mich.), the committee has appealed to voters to contribute to the GOP Victory Fund that supports Republican congressional candidates and to oppose "a massive increase" in taxes spearheaded by Democratic leaders in Congress.

But the envelope containing the fund-raising letter advertises it as "official business" from the House Ways and Means Committee and declares in bold type that the mailing includes "1987 federal tax information." The real return address -- of the NRCC -- appears only on the back of the envelope in much smaller type.

Rep. Beryl Anthony Jr. (D-Ark.), the chairman of the Democratic Congressional Campaign Committee, called the mailing "a sleazy way to raise money" and said the Democratic committee will ask the House ethics committee to investigate whether the campaign violates House rules governing the use of congressional letterheads.

"It's terribly deceptive," Anthony said. "If it's not a clear violation of the House rules, it certainly destroys the spirit of the rules. It's about as flagrant an attempt to impersonate and deceive as anything I've seen."

Vander Jagt, a member of the Ways and Means Committee, which has jurisdiction over tax legislation, could not be reached for comment, but a spokesman for the NRCC said the campaign was "ethical" and "within the bounds of the law."

Vander Jagt's letter, referring to Democratic proposals to raise $18 billion in new taxes, said the tax increase would stifle the nation's economic recovery, precipitate a recession and herald a "return to more big-spending social programs" by the Democratic-controlled Congress.

"It's a proper mailing," said Steven Lotterer, a spokesman for the NRCC. "It gets people's attention on a major issue, that Democrats want to raise taxes and Republicans don't. It's an issue that hits close to home for the Democrats. The more it hurts them, the more they yell."

However, a spokesman for Ways and Means Chairman Dan Rostenkowski (D-Ill.) said he is not thrilled that his committee's name is being invoked on a Republican mailing. Rostenkowski, the spokesman said, had raised the issue with Vander Jagt and was promised the practice would not be repeated.