Former President Joe Biden has endorsed Dan Koh, a candidate running for U.S. Congress in Massachusetts' 6th Congressional District Democratic primary in an open race as Rep. Seth Moulton runs for U.S. Senate.Koh, who served in various roles during Biden's White House tenure, issued a video in which Biden said he was calling because he wanted to endorse Koh.Koh told Biden he is "honored."Biden told Koh, "You will be one heck of a congressman," asserting, "everything you and I fought for, everything we did to help ordinary people is in jeopardy now in this administration, so we gotta get ya elected."DUFFY BLAMES BIDEN-BUTTIGIEG TEAM FOR SPIRIT AIRLINES COLLAPSE AFTER BLOCKED MERGERFormer Vice President Kamala Harris endorsed Koh last year.Koh lost a 2018 Democratic congressional primary in Massachusetts by a razor-thin margin.TRUMP DOJ REPORT LAYS BARE BIDEN ADMINISTRATION'S ALLEGED ANTI-CHRISTIAN BIASBiden also recently endorsed Keisha Lance Bottoms for Georgia governor.KAMALA HARRIS-ENDORSED CANDIDATE IN HOT SEAT FOR MILLION-DOLLAR DC HOME HUNDREDS OF MILES OUTSIDE DISTRICTBottoms, who also served in Biden's administration, had previously served as Atlanta mayor.