Nixon’s rallies sucked but..... he won 48 percent of 18 to 24 year-old voters, 52 percent of under 30 voters, and 54% of voters in labor union families, and the first GOP sweep of the South.
Nixon won 60.7 percent of the popular vote and 520 electoral votes.
He still holds the record as having achieved the widest popular vote margin in any presidential election.
I see FDR got 60.8% popular 1936. Slight edge.