shp2img projection question

[Stephen Gornick]

I am unsure how to get a shapefile (Lat/lon, NAD83) to match, when 
rendered, the boundary outline that I see on Google maps.

To render the shapefile (to a png) I am using shp2img which installed 
with ms4w (1.5.2, which includes mapserver 4.8.3), and the png that was 
created can be seen here:
   http://tinyurl.com/gaucm
Notice that it is "scrunched down" compared to the png that I traced off 
of Google maps, as shown in this image:
   http://tinyurl.com/z89l2
I am assuming the reason this happens is that I am doing projection 
incorrectly -- Google Maps is Lat/lon Mercator.  But I do not know what 
I should do next ... i.e., does the the shapefile need to be converted 
to a different projection first?

The shapefile is the Census' :State and State Equivalent Areas" 
Cartographic Boundary File for MN (st27_d00).
  http://www.census.gov/geo/www/cob/st_metadata.html#meta

My .map is:
*************************
MAP
  NAME MN
  STATUS ON
  SIZE 176 197
  EXTENT -97.238541 43.499504 -89.561234 49.384365
  IMAGECOLOR 255 255 255
  IMAGETYPE PNG

  UNITS METERS
  PROJECTION
    "proj=latlong" "ellps=GRS80" "datum=NAD83"
  END

  LAYER
    NAME BOUNDARY
    TYPE POLYGON
    STATUS ON
    DATA st27_d00.shp

    CLASS
      STYLE
        COLOR 150 150 200
        OUTLINECOLOR 0 0 255
      END
    END
  END
END