Washington ? Wyoming Sen. Craig Thomas, a three-term conservative Republican who stayed clear of the Washington limelight and political catfights, died Monday. He was 74.

The senator’s family issued a statement saying he died Monday evening at National Naval Medical Center in Bethesda, Md. He had been receiving chemotherapy for acute myeloid leukemia.

The family had issued a statement earlier in the day saying Thomas’ cancer had been resistant to his second round of chemotherapy and the senator was listed in serious condition. Thomas was also suffering from an infection, his family said.

Just before the 2006 election, Thomas was hospitalized with pneumonia and had to cancel his last campaign stops. He nonetheless won with 70 percent of the vote, monitoring the election from his hospital bed.

Two days after the election, Thomas announced that he had just been diagnosed with leukemia.