Turnout was down in some states and up in others — notably up in Virginia, where it appeared a higher number voted than in any midterm in the state's history.
It also was a big turnout success for Democrats. They drew more voters than Republicans for the first time in a midterm election since 1990, Gans said Wednesday.
The national figure of slightly over 40 percent turnout this year compares with 39.7 percent in the last midterm in 2002.
National turnout could end up substantially higher, pending more complete numbers from California and Washington state, Gans said. The highest recent midterm turnout was 42.1 percent in 1982.
A key factor in the Democratic takeover of the House, and a factor that drove Democratic voters to the polls, it seems, was the scandals plaguing Republican incumbents.
Nationally, more voters named corruption as an extremely important factor in their House voter than any other issue. Forty-one percent of voters said corruption was as an extremely important factor in their vote, compared to 39 percent who said terrorism and 39 percent who said the economy.
In fiercely contested Virginia — where Democratic challenger James Webb's lead over Republican incumbent George Allen was razor thin and a recount was likely — an estimated 43.7 percent of eligible voters went to the polls, compared to 29.2 percent in the previous midterm.
The last time turnout was comparably high in Virginia was when it hit 43.2 in 1994, Gans said.
Ohioans also came out in substantially greater numbers. Unofficial figures showed 44.3 percent of eligible voters cast ballots compared to 38.4 percent in 2002.
Turnout also was substantially higher in Michigan and Missouri; somewhat higher in Connecticut, Delaware and Kentucky, and slightly higher in Montana, Gans' calculations showed.
It went down substantially in Louisiana because voters there didn't have a statewide race to decide "and because of (Hurricane) Katrina," Gans said. Decreases also were posted in Florida, Georgia and likely Hawaii, he said.