It's actually American bellflower.

http://en.wikipedia.org/wiki/Campanulastrum

Not even close.

Hi Dandy line!

That's beautiful! It appears to be a typical verbascum. I googled it and Dave's Garden has some nice shots. Enjoy!

Here is a link that might be useful: http://davesgarden.com/guides/pf/go/140/

That's a VERY poor pic of American bellflower on that link. No one could ID it by that! But Dandy's right: not even close.

When I grew verbascums I was also unimpressed. Individual flowers were nice, but there would only be few that are similtaneously open, and they only last a day in the sun, sometimes not even. I discarded them years ago. They did, however, last much longer in the shade, but still not to my satisfaction.

Your pic does indeed look like a verbascum, although I don't think there are any MN natives that look like that. I suspect it is a volunteer from someone's garden, although I could be wrong.