The death of Senator Edward Kennedy at age 77 triggered an outpouring of comment on Wednesday, including from Senate majority leader Harry Reid and former first lady Nancy Reagan.
"The liberal lion's mighty roar may now fall silent, but his dream shall never die," said Reid, who like Kennedy is a centre-left Democrat.
Reagan, widow of Republican president Ronald Reagan, referred to her own personal battle for increased public spending on stem cell research, which she believes could help people suffering from Alzheimer's disease, which claimed her husband's life.
"Given our political differences, people are sometimes surprised by how close Ronnie and I have been to the Kennedy family," Reagan said in a statement. "In recent years, Ted and I found our common ground in stem cell research, and I considered him an ally and a dear friend. I will miss him."
Comments from her and other Republicans underlined Kennedy's remarkable ability to work both sides of the political aisle, bringing in conservative support for the major pieces of legislation he is known for in health care and civil rights.
Kennedy's legacy "stands with the greatest, the most devoted, the most patriotic men and women to ever serve in these halls", Reid said.
He noted the major accomplishments attributed to Kennedy's political skill, including health insurance for young children, federal support for needy college students, and Medicare and Medicaid, which provide health care for the aged and poor.