Minnesota GOP activist Ken Kaiser said Grams, 65, was diagnosed with cancer in April 2012 and entered hospice care "within the past couple of weeks," Roll Call reported Wednesday.
"He's still very upbeat, still gets around the house and still has company coming over" to visit him and his wife on the family farm where he grew up, Kaiser said.
Grams is "still pretty good, very tired though," Kaiser said, and recently decided to suspend chemotherapy.
The spokesman said Grams also recently ended his talk-radio show on a station he owns in Little Falls, Minn.
The Grams family does not want the specific cancer revealed, Roll Call said.
Grams went to Washington in 1993 as a GOP member of the House and was elected to the Senate after serving one term in the lower chamber. He returned to Minnesota in 2001, after he lost his re-election bid to Democrat Mark Dayton, now Minnesota's governor.
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