WASHINGTON, D.C. -- On the day presidential senior adviser Karl Rove administered a tongue-lashing to a Republican congressman, disturbing news about his former executive assistant was spread on Capitol Hill. GOP House members learned that Susan Ralston is requesting immunity to testify before Democratic Rep. Henry Waxman's investigating committee.

She was an assistant to Jack Abramoff, Washington super-lobbyist and Republican fund-raiser, in 2001 when he recommended her for the top job with Rove as he entered the White House. As Rove's gatekeeper, Susan Bonzon Ralston became special assistant to the president and the highest-ranking Filipino-American in the administration. For Waxman, she is a link between the disgraced, imprisoned Abramoff and Rove, a principal political target of the Democratic-controlled Congress.

As House Oversight and Government Reform Committee chairman, Waxman is tirelessly making life miserable for a confused administration during George W. Bush's last two years as president. Bringing down Rove ranks high on Grand Inquisitor Waxman's agenda. But Ralston appears to be seeking immunity for self-protection rather than nailing her former boss, and she could be a blank fired by the fierce political marksman from Westside Los Angeles.

Rove, the hard-edged architect of two victorious presidential campaigns, was in the Democratic crosshairs long before Republicans lost control of Congress. Democrats were bitterly disappointed when he was not indicted in the Valerie Plame CIA leak case (when Ralston was among the grand jury witnesses). They have targeted Rove in investigating the dismissal of U.S. attorneys, and the Waxman committee sought testimony from Ralston about Rove's e-mails. She was deposed behind closed doors last month prior to her request for immunity.

Ralston last week told one Republican on the committee that her lawyers wanted her to seek immunity, and another GOP committee member told me she is doing so. According to her friends, she has nothing to say that would cause problems for Rove. Her request for immunity, they explained, resulted from caution by her attorneys. It was forwarded to the Justice Department, whose recommendation may or may not be followed by Congress. Ralston did not return my telephone call.

If her testimony is a dud, that could embarrass Waxman. But he has many other weapons. Since assuming the chairmanship on Jan. 4, Waxman has acted as though he spent the last dozen years in the congressional minority contemplating how many investigations he could launch. His committee has aimed at the General Services Administration, the Food and Drug Administration, constraint of global warming scientists, the misrepresentations of Pat Tillman's death, private contractors in Iraq and the Plame leak, among others.

The Bush team has seemed confused and disorganized in the face of this fusillade. Warnings by Rep. Tom Davis, Waxman's Republican counterpart on the committee, fell on deaf ears at the White House. The president's agents appear uncertain about how much they should meet Waxman's demand for documents.

In such a climate, Rove last week telephoned Rep. Mark Kirk of Illinois to dress him down for allegedly giving the news media an account of a private meeting at the White House in which Kirk and other moderate Republicans complained to the president about his Iraq war policy. "That's not the first time I got blamed for doing what Ray LaHood (a garrulous fellow Illinois Republican House member) did," Kirk told a colleague.

No matter who was responsible for the leak, Rove's scolding of Kirk was not well received in the House Republican cloakroom. Kirk, a former State Department official and U.S. Naval Reserve aviator, is widely popular in the Republican conference. With Waxman hot on his trail and hounding his former assistant, Rove could use enthusiastic support from Republicans on Capitol Hill.

Many of these congressmen believe that Rove should have quit when he was ahead as manager of the two Bush elections and left in January 2005. However, they do not want to see him limp out of Washington with his scalp hanging on Henry Waxman's belt. "We're not hostile to the administration," one prominent conservative House member, who did not want his name used, told me. "We just want it to be over."