WASHINGTON, Sept. 1 (Xinhua) -- U.S. Progressive Democratic Senator Ed Markey, who advocates combating climate change and passing the Green New Deal, defeated House Representative Joe Kennedy III in the Massachusetts Senate primary on Tuesday, showing the progressive strength that is reshaping the Democratic Party.

Incumbent US Sen. Edward Markey speaks, Tuesday, Sept. 1, 2020, in Malden, Mass., after defeating U.S. Rep. Joe Kennedy III in the Massachusetts Democratic Senate primary. (Photo: AP)

"Tonight is more than just a celebration of a movement. It is a real reaffirmation of the need to have a movement, a progressive movement of young people demanding radical change, demanding justice," Markey, 74, told supporters in his hometown of Malden.

The senator's campaign slogan read, "It's not your age -- it's the age of your ideas that's important." His rival Kennedy III is 39 years old.

Markey's primary win paves the way for his expected reelection in November against Republican Kevin O'Connor, The Hill reported.

The result marks the first loss by a Kennedy in a Massachusetts election, the report added.