Geaorgia Bold with Fake Small Caps. Customized.
http://www.myfonts.com/fonts/ascender/georgia/bold/testdrive.html
I really think it is Georgia. They have extended The stem of the P,R,M below the beaseline. They added the decorative serifs to the middle of the stems. I can't find one letter that doesn't match up. Stephen, your suggestions get the same look as the font they are looking for, but I strongly feel that they used Georgia then added the spurs (I don't know the right term).
Also, Georgia is a font used in low resolution situations. That's one of the reasons I went straight to it.
It looks like Boston Truck Style to me.
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