Dewey 44-Thurmond 48 voters

[Urbanbluedog]

Sounds impossible, but there actually seem to have been some in Effingham county Georgia.

Who would they be?

[darklordoftech]

Economically conservative segregationist.

[Asenath Waite]

Tennessee businessman who had run a private power company and was mad about the TVA putting him out of business. Alternatively an ancestrally Unionist Republican (from East Tennessee or Northern Alabama) who nevertheless was extremely racist.

[Podgy the Bear]

What is surprising to me is why Dewey did so well in 1944 in Effingham--getting 46% of the vote when he didn't exceed 20%--either in the state or the adjacent area. 

In any event, a lot of those voters (plus FDR) swung to Thurmond in 1948 for several reasons, not the least of which Effingham is on the SC border.

[Fuzzy Says: "Abolish NPR!"]

Not many.  Dewey viably and visibly opposed the KKK.

The people who might have done this were Texas Regular voters in 1944 and "Presidential Republcans" in the Deep South that saw Thurmond as the real conservative.

[MATTROSE94]

Someone who was either mentally ill, voted for candidates at random,  or somehow became a staunch segregationist sometime between 1945 and 1947.

[morgankingsley]

voted for candidates at random

that would have been epic

[TDAS04]

In Mississippi, Dewey took 6% in 1944, but only 3% in 1948, so it's plausible a handful existed in that state.

[sofaboi]

Effingham was also a very strong county for Herbert Hoover in 1928.

[E-Dawg]

Someone who was either mentally ill, voted for candidates at random,  or somehow became a staunch segregationist sometime between 1945 and 1947.

Why not just a rich segregationist who was very fiscally conservative?

[Gass3268]

I could see someone in East Tennessee voting that way.

[Gustaf]

A very simple answer is tactical anti-Truman voters who knew Dewey couldn't win in the South but Thurmond could and therefore switched to the latter.

[sofaboi]

I could see someone in East Tennessee voting that way.

There don't seem to have been very many there though. Dewey still swept East Tennessee and Thurmond got single digits there.

[darklordoftech]

Murray Rothbard if he was old enough to vote in both elections.