As you can see with this video provided, it's a 100% fact:

[link to www.youtube.com]

Van Buren is the only president not related to John Lackland. Why did he get elected? A fluke? He was a one term president and this just happened to happen when he was in office:
The U.S. had several problems during his term. Soon after he became President, hundreds of banks failed causing financial panic. What do you know. This is after he was vice for Andrew Jackson who went against the baknking system and almost got killed.

His running mates: William H. Harrison, Hugh L. White, and Daniel Webster

This brings me to 2 big questions.

1. Were any of Van Buren's rivals in the election related to John Lackland.

2. Is Mitt Romney related to John Lackland.