The left, predictably, says this type of talk is "dangerous" to the integrity of our electoral system, and then glibly asks for Mr. Trump to prove his voter fraud allegations.

This is where the left is wrong: The argument isn't whether voter fraud is real, but how widespread it is. Here's 10 examples documenting that voter fraud isn't a myth and how Mr. Trump's claims aren't just speculation.

1. Dead people voting in Colorado.

A CBS affiliate's evidence of voter fraud in Colorado in September sparked an immediate investigation by Secretary of State Wayne Williams. A report in Denver exposed multiple incidents in recent years where dead Coloradans were still voting. A dead World War II veteran named John Grosso voted in a 2006 primary election, and a woman named Sara Sosa who died in 2009 cast ballots in 2010, 2011, 2012 and 2013. Mrs. Sosa's husband Miguel died in 2008, but a vote was cast in his name one year later.