LBJ is convinced to put wartime press controls up as Truman did in Korea. Abrams takes over a year and a half earlier and convinces LBJ to let up on the day to day control. He also better manages the press. A Tet on steroids backed up by three times as many NVA regulars hits in 1968, but there is no Cronkite the war is lost moment that breaks LBJ’s will.
Tet itself OTL increased support for American escalation for many weeks as does the Tet on steroids, but the media treats it very differently, more akin to a Battle of the Bulge moment. Nixon doesn’t run on ending the war, but like Ike in ‘52 runs on ending it on America’s terms.
LBJ has another heart attack during the campaign and Nixon wins a close election. Nixon goes with one of the middle of the Pentagon’s options for the war which roots out the insurgency faster and builds the ARVN faster. There is a Soviet and Chinese backed armistice set up in 1972 after a Linebacker on steroids air raid that allows foreign forces to stay in South Vietnam and the war turns into border guards watching each other with binoculars like Korea.