Kamala Harris vetting about a dozen possible VP candidates

Approximately a dozen individuals are being vetted as possible running mates for Vice President Kamala Harris, according to a source familiar with the process.

That number is larger than previously reported, and is an indication that the campaign is casting a wide net at the start of this process and isn't winnowing the list yet.

Multiple sources tell CBS News that the list of candidates includes several governors: Josh Shapiro of Pennsylvania, Roy Cooper of North Carolina, Andy Beshear of Kentucky, Tim Walz of Minnesota, J.B. Pritzker of Illinois and Gretchen Whitmer of Michigan.