All three of the major indices closed lower, the Dow losing 185 points. Investors are watching the fights in Congress closely.
It's a game they've seen played out before: 776 days ago, a similar fight cost the United States its top credit rating, sending stocks lower and eroding consumer confidence.
And that was just the downgrade.
What would happen if the government actually shut down?
OutFront: Mark Zandi, Chief Economist at Moody's Analytics.