From NPR News, this is ALL THINGS CONSIDERED. I'm Audie Cornish. The stage is set in Denver for the first presidential debate tonight at 9:00 p.m. Eastern. The candidates are suiting up, reporters are gathering, live tweeters are sharpening their virtual pencils. And NPR's Mara Liasson is in Denver and she joins us for a preview. Welcome, Mara.
MARA LIASSON, BYLINE: Hi, Audie.
CORNISH: So what is the format for tonight's debate?
Economic sanctions have a reputation for being the international equivalent of a slap on the wrist. But in Iran, there's evidence that they are working, and that the country's flamboyant President Mahmoud Ahmadinejad might pay the price.
In the past year, Iran's currency has shed 80 percent of its value against the dollar, dropping by 25 percent in just the past week. That's caused a scramble for the few U.S. dollars available in the black market as people seek a safe haven against the free-falling rial.