The Senate session is coming to a close for the 113th Congress, and we are seeing a dramatic change in its composition come January 2017. Liberal firebrands Harry Reid, Barbara Boxer and Barbara Mikulski will be retiring, leaving quite a big void in the chamber   but they will all be succeeded by equally progressive leaders, so no need to worry.As per tradition, the outgoing members of the Senate gave their farewell addresses on the floor, speaking for the last time in their capacity as Senators. Needless to say, it was bittersweet watching these leaders (who have been in the Senate for over 25 years) pass the torch. But while watching their remarks   and their colleagues  tributes   we are reminded of all the handwork they did for the progressive causes we as Democrats hold so dear.Here are their farewell addresses.Barbara BoxerSenator Boxer has served in the Senate since 1993 for California, and beforehand in the House from 1983 until joining the Senate. She chaired the Senate Environment Committee before becoming a ranking member. A pro-LGBT (before it was acceptable), pro-worker s rights, pro-environmentalism senator, Boxer never wavered in her fight for what was right for not only California but for the whole country.Barbara Mikulski Senator Mikulski, the longest-serving woman in Congressional history, arrived in the House in 1977, serving until moving up to the Senate in 1987. She chaired the powerful Appropriations Committee, becoming a ranking member. Coining the term  Macaroni and cheese economics,  Mikulski worked tirelessly for working families, children, women, and veterans, who too often fell prey and victim to a system that was rigged against the little guys.Harry ReidSenator Reid, who entered the United States Congress in 1983 and the Senate in 1987, bringing with him a unique and humbling story of hope, handwork and perseverance. For two years Reid served as Minority Leader until elevating to Majority Leader, a position he held for 8 years   in which he fought tooth and nail to protect and defend President Obama s legacy and the progressive ideals the Democrats work for every single day. Whether it be standing up to Ted Cruz during a government shut down, or convincing centrist Democrats to vote in favor of Obamacare, Harry Reid never backed down   ever. And we are better as a nation because of that.These three progressive Senators blazed trails and put up the good fight. When the going got tough, the tough got going. Senators Boxer, Mikulski and Reid stood tall in times of thick and thin, and never wavered in their commitment to doing the right thing. These Senators will be missed greatly, and their legacies will live on long after they leave their seats. There might never be more like them, but we should all feel lucky that each one will be succeeded by intelligent, equally compassionate progressives who share their values.Harry Reid, Barbara Boxer, and Barbara Mikulski   you will be greatly missed. Thank you for your service.Featured image via Alex Wong/Getty Images