Update: 6:22 pm: ABC has exit polls up .

Update 6:00 pm: 93% say the economy is really bad, but 47% say it will get better. On taxes, 70% say Obama will raise taxes, 61% say McCain will. (This matches a poll that was released earlier this week.) Update: 5:40 pm: New voters: In every state, they went to Obama. 72% of new voters voted for Obama.

Update: 5:30 pm: Terrorism, 9% of voters said it was their main issue. Of them, McCain led 86% to 13%. In PA, 88% of those voters chose McCain, 12% Obama. McCain led with these voters in all the states they showed. My view: Who in their right mind thinks terrorism is the top issue, over the economy? These are clearly fringe voters, happily, there are only 9% of them.

Update 5:14 pm: Iraq: Concern about the war helped Obama. Among the 10% who said they were most concerned about it, 63% voted for Obama, 36% for McCain. Obama won voters most concerned about Iraq in 48 states, the exceptions were Kentucky and one I couldn't read.

5pm ET, CNN is about to announce first exit polls. I'll update.

Top Issue: The Economy, 62% said it's the top issue on their minds. Iraq? 10%. Terrorism, health care: 9%.

The exit polls are done at the polling places. They get a questionnaire. Every sixth or so voter gets them.

What about those who mailed in their ballots or early voters? No exit polls, but they are telephoned, land line or cell, and asked the same questions.

CNN's exit polls will be available here.

First polls close at 6pm ET.