We've been hearing about the inevitable "blue wave" handing control of the House of Representatives to Democrats since before President Trump was inaugurated.  Maxine Waters, for one, gained the sobriquet "Auntie Maxine" for offering the political equivalent of bedtime stories promising impeachment on the come, once voters corrected the obvious error they committed by electing Trump.  History, after all, dictates that the president's party loses support, and the GOP's margin in the House is smaller than the historic average.

Polls continue to predict a blue wave, albeit one that might be too small for surfers.  But polls depend on constructing a model of the expected turnout and then finding respondents to match the model: a certain percentage of Republicans, independents, and Democrats.  If the pollsters fail to accurately predict which kinds of voters will be motivated in an off-year election, their polls are useless.

That hasn't stopped them from offering their own versions of the odds favoring the Democrats to take over the lower chamber.  Nate Silver, who remains the media's favorite polling guru despite offering overwhelming odds of a Hillary Clinton win in 2016, puts the odds of a Democrat speaker of the House next year at nearly the same level of certainty: 85%.

But people who put their money on the line in making predictions question the pollsters.  William Cummings, writing in USA Today, writes:

The odds on MyBookie favor Republicans maintaining hold of their majority, even as political forecaster Nate Silver says there is an 84.9 percent chance of a Democratic victory. 

As of Sunday, the odds of the GOP keeping the House are at -140.  That means you would need to bet $140 on the Republicans to win $100 if they stay in the majority.  The Democrats are at +110, meaning a $100 bet would win you $110 if the Democrats manage to wrest control of the House. 

The site also has the Republicans favored to hold the White House in the 2020 presidential election.  The GOP is at -170 in that race, compared to +130 for the Democrats.

Nothing is certain, and the people wagering on the election don't necessarily have the best data.  What they do have is an interest in winning, and large numbers of people sensing and evaluating data and making a judgment call.

The pollsters may be right this time, unlike 2016.  Maybe they have reflected on their errors and honestly appraised what they missed last time with an appropriate level of self-criticism.  If that is your impression of what the journalistic community (which employs the pollsters whose results are made public) has done, then you should have more confidence in the pollsters.  

Otherwise, maybe the bettors have a better sense of what's ahead.

Whom are you going to trust?  The guys who got it wrong last time or the people who put their money where their mouths are?