Perhaps that is because there's no evidence Clinton has made any progress in bringing those hearings about.

When she called for the hearings, she said she was doing so because the issue was urgent, and "I'm not going to be president for 18 months."

She also said she had the ability to get the hearings scheduled as a member of the Senate Environment and Public Works Committee.

At the time, the committee's chairwoman, Sen. Barbara Boxer, D-Calif., was reported to have agreed to schedule the hearings soon after the Senate reconvened in September.

September has come and gone and there has been no word on the proposed hearings. Nothing on Yucca is on the committee's published agenda.

The agenda goes only through Wednesday. But preparations for hearings typically begin further in advance, and aides said there does not appear to be any Yucca hearings in the works.

"At this time, we are unaware of any plans for the committee to hold hearings on Yucca Mountain," Republican committee staffer Matt Dempsey said.

Clinton spokeswoman Hilarie Grey said Clinton put in a request for the hearings and is "hoping to get a date very soon."

"She requested the hearings, and she wants to have the hearings," Grey said.

Clinton's Senate office is "working with Senator Boxer's office to get the hearing scheduled."

Boxer's Senate office referred inquiries to the committee office. Over two days of repeated inquiries, a Democratic committee spokesman did not follow through on a promise to find out the status of the request for Yucca hearings.

Clinton clearly is following the issue. In Wednesday's debate, she picked up on a remark by Rep. Dennis Kucinich, D-Ohio, that he was "one of the few up here who actually spoke against having a nuclear dump in Nevada."

When it was her turn to answer moderator Tim Russert's question about nuclear power, Clinton said she wouldn't rule out expanding it, "but it would not be one of the options that I favor unless, No. 1, the cost can get down for the construction and operation; No. 2, that we have a viable solution for the nuclear waste."

She continued, "I voted against Yucca Mountain. I've spoken out against Yucca Mountain. I think that recently the discovery (that) there's an earthquake fault going under the proposed site at Yucca Mountain certainly validates my opposition."

Clinton's commitment to stopping Yucca has been questioned before. When she first called for Senate action, Sen. James Inhofe, R-Okla., accused her of having been "missing in action" when two hearings on Yucca and nuclear waste were held in 2006.

Inhofe, who backs the Yucca repository, chaired the committee at that time. Since Republicans became the minority in the Senate this year, he has been the committee's top Republican.

Clinton's campaign responded that she had scheduling conflicts with the 2006 hearings, including a hearing on assistance for AIDS patients and a meeting on international women's rights.

Clinton also said that Democrats were in a better position than before to "ask the hard questions" now that they have the majority in both houses of Congress.