Which brought about Nixons downfall after he had won reelection in a landslide?

Nixon's downfall after his landslide reelection was primarily due to the Watergate scandal, which involved a break-in at the Democratic National Committee headquarters and subsequent cover-up efforts by his administration. Investigative journalism, particularly by reporters from The Washington Post, revealed the extent of the scandal and led to public outrage. As evidence mounted, including the infamous tapes that captured Nixon's involvement, he faced increasing pressure to resign. Ultimately, facing imminent impeachment, Nixon became the first U.S. president to resign from office in August 1974.