I'm working on a business card design that features the client's vibrant, cobalt blue. Of course, if converted to CMYK, this blue changes to a dull blue gray, so I instead used a Pantone spot color. But when I generate a PDF of the InDesign document, the vibrant blue resembles what it would look like if I had converted it to CMYK -- dull grayish blue. Does the PDF export process utilize a CMYK conversion of some kind? Is this PDF an accurate portrayal of what the final, printed piece will look like?

-Ray