Elizabeth Edwards (search), wife of former Democratic vice presidential candidate John Edwards (search), thanked supporters on Thursday for their thoughts and prayers as she battles breast cancer.

"Your strength is carrying my family through, too, in this latest struggle," she wrote in an e-mail. "This is a fight we will win."

A biopsy has shown that a half-dollar sized lump in her breast has not spread, a family spokesman said, as Edwards began chemotherapy.

After a 16-week chemotherapy course, Edwards will take a four- to six-week break. Georgetown University Hospital doctors who are treating Edwards will then surgically remove the lump.

A needle biopsy of Edwards' lymph nodes Tuesday found "no indication of cancer," spokesman David Ginsberg said. "From what we know now, it has not spread."

As a safety precaution, however, doctors will remove some of her healthy lymph node tissue. Edwards will then undergo radiation.

The mood at the Edwards household was upbeat. Well-wishers have written to say "they know she's strong and she's going to fight through this and their thoughts and prayers are with her," Ginsberg said.

Edwards, 55, said she discovered the lump in her right breast on Oct. 21, during a campaign trip. She said she had not gotten a mammogram in recent years.

She was diagnosed with invasive ductal cancer (search), the most common type of breast cancer, which can spread from milk ducts to other parts of the breast.

Well-wishers can send e-mail to Elizabeth@oneamericacommittee.com or can send cards to Elizabeth Edwards, P.O. Box 75428, Washington, DC 20013.