In an interview with USA Today that is already becoming one of the day's hot items, Hillary Clinton told the paper that she has "a much broader base to build a winning coalition on" than Barack Obama does. And she referred to an Associated Press article that, she said, "found how Sen. Obama's support among working, hard-working Americans, white Americans, is weakening again, and how whites in both states who had not completed college were supporting me."

"There's a pattern emerging here," Clinton added.

This kind of argument coming from her isn't surprising -- as the Clinton camp has found itself in ever more dire straits, it has made ever more unsubtle arguments about the demographics of the campaign. But just because it isn't surprising doesn't mean it isn't silly.

There are two problems with what Clinton said. First, there's the assumption that voting patterns in the primaries accurately predict voting patterns in the general election. That's not a good place to start an argument from.

But even if we concede the above point, there's still the matter of the unspoken demographic problem Clinton herself faces. African-American voters are absolutely critical to the Democratic Party. And while it's true that Obama trails behind Clinton in winning support from white working-class voters, it's not as if he's getting no support from that group whatsoever. Clinton, on the other hand, has almost no support left from African-American voters. Even George W. Bush captured a larger share of the African-American vote than she has in some recent primaries. In 2004, Bush got 11 percent of the African-American vote. In the Indiana Democratic primary on Tuesday, Clinton got the same percentage Bush did in '04 -- in North Carolina, though, she took just 7 percent.