Senate Democrats and affiliated outside groups are outspending their Republican counterparts by an almost two-to-one margin on television in the final week of the tight-as-a-tubesock special election between state Sen. Scott Brown (R) and state Attorney General Martha Coakley (D). The Democratic Senatorial Campaign Committee is now committed to nearly $1 million in television ads in support of Coakley while the Service Employees International Union ($529,000) and Citizens for Strength and Security ($278,000), a labor-backed 527 group, are also spending heavily. The National Republican Senatorial Committee is not on television in the state although the Chamber of Commerce ($443,000), American Future Fund ($375,000) and Americans for Responsible Health Care ($204,000) are combining to spend just over $1 million for Brown.