If you think Donald Trump can’t win in November, think again.

Educated opinion may dismiss the big blowhard’s chances as negligible, but the bookies think otherwise — and unlike the rest of us they have to put their money where their mouth is.

Oddsmakers are giving Trump a disturbingly large 30% chance or more of becoming the next U.S. president, according to several online sites both here and overseas. Hillary Clinton, the presumptive Democratic nominee, gets the balance — somewhere between 61% and 70%, depending on the oddsmaker.

Ladbrokes, the London-based bookmaking giant, is taking bets on Trump at odds of 9/4, equivalent to giving Trump a 30% chance of winning. Rivals such as William Hill and Bet365 are offering Trump at 2/1, equivalent to a 31% chance. Here on U.S. soil, gamblers at the University of Iowa’s “Electronic Market” are giving Trump around a 30% chance, while those at Predictit.org put his odds as high as 40%.

Donald Trump's odds of winning the White House - Predictit.org, May 4. Predictit.org

As a general rule, the major sportsbooks on the elections are run from abroad, especially from London. U.S. laws make it nearly impossible to run books here. Iowa and Predictit run limited stakes books through special, legal exemptions granted by the U.S. government.

Betting markets are far from perfect. Only naïve fools still believe in the so-called “wisdom of crowds.” But betting odds can’t be dismissed lightly either. Those who think they can beat the market easily should try it.

Opinion Journal: The Republican Party’s leap of faith

Yes, of course Hillary Clinton ought to crush Donald Trump in a landslide in November.

Rationally, the former First Lady, senator, and secretary of state ought to beat the unqualified and preposterous New York carnival barker hands down. But Hillary Clinton is the Bill Buckner of politics. She can flub the easiest ground ball. Just watch. (Actually, that comparison is totally unfair to Buckner — a distinguished player who only flubbed the ground ball once. Hillary Clinton’s unforced errors, on the other hand, just seem to come and come.)

Clinton should have dispatched Senator Bernie Sanders months ago. Instead she is still chipping away, state after state. Without the help of her pals among the super delegates it would be a genuine contest. Watching it is painful or hilarious, depending on your point of view.

And if this is how she handles the senator of Ben & Jerry’s, how will she perform against Trump?

Hillary Clinton still has to deal with nagging questions about her emails, and high negatives among voters. And Trump has proven an extraordinary master of propaganda. I am among many who assumed his campaign would implode months ago. Oh boy. Instead, in the last six months he has dispatched a lot of strong political rivals.

Can we write Trump off over the next six months? Don’t count on it.