The aid from the Senate Conservatives Fund follows Akin's endorsement Wednesday by DeMint and former Republican presidential candidate Rick Santorum, whose Patriot Voices political action committee said it was contributing money to Akin and hiring staff to work in Missouri. The Freedom's Defense Fund, which backs conservative candidates, also said earlier this week that it planned a $250,000 advertising campaign benefiting Akin.
But Akin will need even more outside help to keep pace with Democratic-leaning groups supporting McCaskill.
Emily's List and the Service Employees International Union issued a joint statement Thursday saying they had bought $1 million in ads in support of McCaskill to run in the state's largest TV markets.
The Democratic Senatorial Campaign Committee, which already has spent about $1 million on TV ads in Missouri, has reserved $4.3 million of additional advertising to begin running Oct. 9.
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