Is that bizarre conspiracy theory more likely or that their search results scrape Wikipedia and return the most recent party a politician belonged to?
https://en.wikipedia.org/wiki/Abraham_Lincoln
Lo and behold, it reports that Strom Thurmond was a Republican (https://en.wikipedia.org/wiki/Strom_Thurmond) and Jeff Van Drew is too (https://en.wikipedia.org/wiki/Jeff_Van_Drew), even though both were Democrats for substantial periods in the past.