The 'Stronger' singer was forced to defend her support of the politician via Twitter on Thursday after many of her followers cited examples of Paul's alleged homophobia and racism.
"I am really sorry if I have offended anyone. Obviously that was not my intent. I do not support racism. I support gay rights, straight rights, women's rights, men's rights, white/black/purple/orange rights," she wrote.
"I like Ron Paul because he believes in less government and letting the people (all of us) make the decisions and mould our country. That is all. Out of all of the Republican nominees, he's my favourite."
Online retailer Amazon has since reported a 192% increase in sales in the 24 hours following Clarkson's endorsement of Paul.
Clarkson's fifth studio LP Stronger was listed at number 41 on Amazon's album chart prior to the tweets but has since risen to number 14.
> Kelly Clarkson announces North American dates for Stronger tour 2012
Watch Kelly Clarkson's video for 'Stronger' below: