At a recent Sotheby's auction, Lincoln's heartfelt letter of thanks to school children set a record for a presidential manuscript. It sold for $3.4 million

In August of 1858, Abraham Lincoln became known around the United States as he debated slavery with Senator Stephen Douglas. Those debates would not help Lincoln win a U.S. Senate seat, but they would eventually help him win the presidential election just two years later.

Now, copies of those debates signed by Abraham Lincoln are among the most popular, and rarest of presidential collectables. 

VOA's Kane Farabaugh reports from Lincoln's home state of Illinois that artifacts from the 16th U.S. president are as popular as ever among collectors.