why McCain is losing?

As Steve Hayes notes, back in 2007 the most important issue in picking a president for both Republicans and Democrats were national security related—terrorism for Republicans, Iraq for Democrats. Now only nine percent cite terrorism and seven percent Iraq as their top issue while 57 percent name the economy. This isn’t surprising given recent events but it does make it extremely hard for McCain to breakthrough. His greatest strength as a candidate is national security, something that his war hero biography reinforces. It is the subject on which he is most passionate and knowledgeable. By contrast, McCain used to admit rather too candidly that he didn’t know as much as he should about economics. (Spectator)