DETROIT -

A hoax telling voters what to do while in the voting booth is spreading on Facebook.

The post says:

"For those voters who are Democrats to "not select the button 'all Democrats' first, because Barack Obama will be excluded from the vote. However, if we choose 'Barack Obama' first, and then 'all Democrats' he will earn our votes!!!"

The problem is, that is the opposite of what voters should be doing in some specific cases.

---Message making the rounds on Facebook is a hoax

In some states, "choosing the party first on a voting machine can lead to all of the candidates of your preferred political party being chosen — including the presidential candidate," wrote Graham Cluley, senior technology consultant for Sophos Security, on the company's Naked Security blog. "That could mean if you get confused and subsequently make a presidential selection for a second time, you could uncheck your vote for the president." 

Facebook, contacted by NBC News, declined to comment.