WASHINGTON — White House political adviser Karl Rove raised questions in early 2005 about replacing some federal prosecutors but allowing others to stay, an email released yesterday shows.

The one-page document, which spans e-mails between the White House and the Justice Department in January 2005, also indicates Attorney General Alberto Gonzales was considering a range of options in dismissing U.S. attorneys early in President Bush’s second term.

Meanwhile, a Senate panel authorized subpoenas for Justice Department officials yesterday and raised questions about White House involvement. A second Republican senator urged Mr. Gonzales’s departure.

Subpoenas for President Bush’s top aides, including Mr. Rove, could be approved next week.

One Republican, Senator Sununu of New Hampshire, has publicly urged Mr. Bush to fire Mr. Gonzales. A second, Senator Smith of Oregon, said yesterday that Mr. Gonzales had lost the confidence of Congress.

“The senator believes it would be helpful to have an attorney general that Congress can have more confidence in,” said Mr. Smith’s spokesman, R.C. Hammond.

Still another Republican, this one in the House and not ready to speak out publicly, said he planned to call for Mr. Gonzales to step down.

Other Republican lawmakers spent yesterday urging colleagues to refrain from joining that chorus until they hear more from Mr. Gonzales and his aides directly.

“Let’s give them a chance to respond before we get tough,” said Senator Specter of Pennsylvania, the senior Republican on the Judiciary Committee. “I’m prepared to get tough, but I want to get tough with a basis for doing so.”