Washington is amok in political prognosticators. The sheer volume of fresh polling data available on a daily basis would fill the Potomac and Chesapeake Bay combined.
Firms that scrutinize how Americans surf the Web can tell whether they're likely to vote Republican, Democrat or not at all. And statistical gurus tout the latest high-tech models for predicting electoral outcomes.
Yet, with five days to go, there isn't a disinterested observer of the American political scene willing to risk a reputation by calling this one.
The Nov. 2 midterm congressional election is shaping up to be one of the strangest in memory, with a host of contradictory signals leaving even the most seasoned analysts hedging their bets about the final outcome.
The raw polling data suggests Americans may be poised to turf out the largest number of incumbent members of Congress in more than 70 years. Yet, the midterms could also produce a historical anomaly if, as expected, Democrats lose the House of Representatives but retain the Senate.
"There is this historical precedent that is bothering us," Jennifer Duffy, senior editor of the highly regarded Cook Political Report, explained in an interview. "The House majority has never changed without the Senate changing, too."
Based on raw polling alone, the stage is set for a GOP tidal wave next week. For instance, Republicans lead Democrats by 55 per cent to 41 per cent among likely voters in the latest Gallup "generic ballot" poll.
A USA Today/Gallup poll released Tuesday shows that 63 per cent of registered voters who are Republican or lean Republican are "more enthusiastic than usual" about this election. On the Democratic side, only 37 per cent say that, producing a midterm "enthusiasm gap" three times wider than the 9-point difference that proved fatal for Democrats in 1994.
Still, analysts remain cautious about whether Republicans will gain just enough seats - 39 - to take control of the House or pick off nearly twice that many Democratic districts.
"House Democrats face the potential of a political bloodbath the size of which we haven't seen since the presidency of Franklin Delano Roosevelt," Rothenberg Political Report editor Stuart Rothenberg wrote Tuesday in the Capitol Hill newspaper Roll Call. "If the patterns of past years hold, Republican gains could well exceed those of 1994."
Yet, not even he is prepared to say they will. For all anyone knows, the GOP wave may have already crested.
In 1994, Democrats lost 52 House seats and Republicans won both chambers of Congress. In 1938, Republicans gained 71 House seats and 17 in the Senate. Democrats, however, kept control of both houses that year, since the party had built up massive majorities in previous elections.
Both the 1994 and 1938 results, however, were consistent with historical precedent. Typically, when the House falls, so does the Senate.
(There is one possible exception. After the 1930 midterm race, a series of special elections gave Democrats a one-seat majority in the House by the time Congress convened in 1931. Republicans held the Senate.) How can it be, then, that Republicans are still likely to fall short of the 10 seats they need to gain to take the Senate next week?
Ms. Duffy has a couple of ideas. One relates to the particular slate of Senate seats up for grabs this year. Republicans are usually not even contenders in bluish states such as California, Washington and Wisconsin. That incumbent Democratic senators Barbara Boxer, Patty Murray and Russ Feingold are all facing the toughest battles of their careers is a testimony to the GOP's momentum in 2010.
Then there is the O'Donnell factor. Tea Party-backed Republican insurgents such as Christine O'Donnell in Delaware, Joe Miller in Alaska and Sharron Angle in Nevada may not just be doing damage to themselves with their gaffes and out-of-the-mainstream ideas. They may also be scaring off potential GOP voters in other states.
Though a poll out Tuesday placed Pennsylvania GOP Senate candidate Pat Toomey well ahead of his Democratic rival, other surveys have showed his lead collapsing since Ms. O'Donnell won the GOP nomination in neighbouring Delaware last month.
"The voters in Pennsylvania are seeing O'Donnell's ads. They're seeing her in the news. They're getting a big dose of her," Ms. Duffy said, noting that the Philadelphia media market covers Delaware.
It's still possible the GOP could hit the magic number and win the Senate. Most races remain too close to call. And the National Republican Senatorial Committee pumped $3-million into the California race on Monday to run a new TV ad attacking Ms. Boxer. The investment suggests the GOP still thinks its candidate, former Hewlett Packard chief Carly Fiorina, can win that contest.
Still, the odds are that the 2010 midterms will render a split decision. For once, as the House turns, the Senate may not. Can you call that a wave?