Sen. Hillary Clinton is up with a radio ad in South Carolina today, her first. A few things of note:

## It's targeted at African American women. She purchased 140 gross ratings points in Florence, 165 points in Chucktown, 400 in the capital of Columbia, and 180 in Greenville. It's estimated to have cost the campaign about $40,000.

## The ad references the Corridor of Shame, an underfunded, underperforming, largely minority stretch of rural school districts along I-95 in South Carolina.

## It keeps with the "Invisibles" theme that Clinton has employed in the early primary states. October is Invisibles month for the Clinton campaign, so expect to hear a lot more from Clinton on the subject.

## In South Carolina, undecided black women will probably determine the outcome of the primary. A recent poll of the African American electorate in South Carolina suggests that Clinton may be losing some ground to Obama.

Anncr: Hillary Clinton has spent her life standing up for people others don’t see.
Hillary: Too many Americans today feel as though they are invisible... If you are a child in a crumbling school along the Corridor of Shame, you ARE invisible to this president.
Anncr: Thirty-five years as a tireless advocate for children and families…
Hillary: If you’re a mother without health care, a father without a job, a family that can’t get by on the minimum wage... you’re invisible as well.
Anncr: Time and again, Hillary Clinton has stood up to President Bush…stood up FOR us.Hillary: And if you’re stuck on a rooftop or stranded in the Superdome during a hurricane you’re invisible to this president even when you’re on CNN. Well, you are not invisible to me, and you should never be invisible to the president of the United States.
Anncr: Hillary Clinton. If you’re ready for change. She’s ready to lead. Paid for by Hillary Clinton for President.
Disclaimer: I’m Hillary Clinton and I approve this message.

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