Post-WW2 elections with a runoff (no EC)

[Sir Mohamed]

Let's assume the electoral college had been abolished after World War 2 and we switched to a direct PV election with an absolute majority necessary. Assuming all elections end up with the same popular vote result as in real life, what had happened in these contests, in which the "winner" received less than 50% and a run-off would have been held? These elections were 1948, 1960, 1968, 1992, 1996, 2000 and 2016.

My predictions:

1948
✓ Harry S. Truman: 51.9%
Thomas Dewey: 48.1%

1960
✓ John F. Kennedy: 50.4%
Richard Nixon: 49.6%

1968
✓ Richard Nixon: 51.0%
Hubert Humphrey: 49.0%

1992
✓ Bill Clinton: 51.6%
George Bush: 48.4%

1996
✓ Bill Clinton: 55.0%
Bob Dole: 45.0%

2000
✓ Al Gore: 51.1%
George W. Bush: 48.9%

2016
✓ Hillary Clinton: 52.0%
Donald Trump: 48.0%

[Mr. Smith]

1948: Truman 51-48
1960: Kennedy 50-49
1968: Nixon 51-48
1992: B. Clinton 53-47
1996: B. Clinton 55-45
2000: Bush 50-49 (Panhandle Florida votes give Bush the edge)
2016: Tossup. H. Clinton favored.

EDIT: Initially had H. Clinton for 2016, but I don't see any kind of way the run-off doesn't just become another battle of scandals with the winner simply being who comes out on top. 2016 was pretty much a coin toss as is.