France’s support for Trump is controversial, given the candidate’s xenophobic stands against Muslims, Latinos and, through his supporters’ actions, blacks. However, Trump’s greatest strength appears to be among members of NASCAR’s primary fan base — white working-class people.

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Criticism of France arose soon after he announced his support for Trump. Monday’s media event came a day after the candidate failed to disavow support from a well-known Ku Klux Klan figure.

NASCAR is trying to broaden its appeal and its field of competitors through diversity efforts. However, there are no black drivers in Sprint Cup, its top racing series. There are several minority crewmen across three national racing series, and some Hispanic drivers. There is only one black driver, however — Darrell Wallace Jr.

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Now comes word that France sent an email to NASCAR employees saying his support for Trump is personal and not from the sport he oversees.

In an email obtained by Motorsports.com, France told employees:

That follows an email cited by The Charlotte Observer, based less than a mile from NASCAR’s North Carolina headquarters, from France lieutenant David Higdon.

Higdon, the racing organization’s top communications executive, told The Observer via email that France’s endorsement was a “personal, private decision by Brian.” France, he wrote, has a history of support fro Republican candidates. However, reports say this is the first time France has endorsed a presidential hopeful.

The Observer also noted that France’s grandfather, NASCAR founder “Big Bill” France, endorsed former Alabama Gov. George Wallace in the late 1960s and early ’70s.

Wallace was among Southern governors who made notorious stands in support of segregation. In his 1963 inaugural address, Wallace said: “Segregation now, segregation tomorrow, segregation forever.” While he would soften his stand publically, Wallace would be tied to that statement the rest of his life.

In his email to employees, France wrote that NASCAR would continue its diversity efforts to grow its fan base and “make our sport more open and friendly to everyone.”

Among those critical of France’s stand is Marcus Lemonis, chief executive of Camping World — the company that is title sponsor of NASCAR’s Trucks series. Lemonis was born in Lebanon. He has been openly critical of Trump for “blatantly bigoted and racist” comments about Latinos.