Sure, there's been some action on TradeSports.com and the Iowa Electronic Markets on who will win tonight, but it's nothing like 1916, when the NY markets tallied $158 million (in 2000 dollars) in election wagers. Eventually, the NYSE and other markets barred members from engaging in election gambling. From the WSJ's Marketbeat:

"The New York betting odds received substantial media coverage in the era before scientific polls," wrote Paul Rhode and Koleman Strumpf, economics professors at the University of North Carolina-Chapel Hill. "These historical markets are of special interest because partisans, including Democratic and Republican party operatives, actively and publicly traded. Accusations of manipulation and bluffing were rife."

At last check, the odds of the Dems taking over the House were running over 80 percent, while the odds of the GOP holding the Senate were 67 percent. The betting markets have proven pretty reliable over the years. The IEM is especially good; in 2000 it predicted that Al Gore would win the popular vote.