Just weeks ago, it looked as if Sanders' formidable digital fundraising operation would provide him with an insurmountable resource advantage and the ability to compete on the airwaves in states that only self-funding billionaires could access. However, almost overnight, Biden's victory in South Carolina launched his fundraising and national polling averages into overdrive. He could suddenly compete with Sanders' resources, and he utilized his influx of cash to air ads in key states touting his electability and relationship with Barack Obama. During the week of February 18th Sanders outspent Biden by $4.8 million. Two weeks later, he was only ahead by only $1 million. Sanders' lead in reservations for the week of March 10th extends back to $2M, but Biden has time to reserve more ads and close this gap.

"Big Tuesday" States

The two candidates have spent a cumulative $5 million on "Big Tuesday" with Sanders holding a $700 thousand advantage. Biden, however, has small spending advantages in both Missouri and Mississippi and is only a few thousand dollars behind Sanders in the critical state of Michigan. Sanders

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