In a little over seven months, Americans will choose a successor to Barack Obama. America’s first black president could be succeeded by the first woman to hold that office. The Republican Party’s primary race is down to just two viable candidates, the property tycoon Donald Trump and Texas senator Ted Cruz. The Democratic nomination looks destined for Hillary Clinton, although her last remaining rival Bernie Sanders is not out of the picture. The betting is that Clinton would beat either of the Republicans in November.

Media coverage of the Republican race in Europe has focused on Mr Trump, whose proposals include a wall between the USA and Mexico (the border is 3,140 kilometres long) to be paid for by Mexico, the expulsion of all illegal immigrants and the exclusion of Muslims from the United States.

Less attention has been paid to Senator Cruz, who also favours the Mexican wall, expelling the undocumented and a few other things besides. One of these is the return of the gold standard (basing the dollar on the value of gold), abandoned almost half a century ago.

The University of Chicago polled 50 top American economists on the issue and unusually they all agreed: it’s nuts. Senator John McCain, who lost to Obama in 2008, has described Cruz as “a wacko bird”.

There are few policy differences between Trump and Cruz. Either would be further from the political mainstream than any Republican candidate since Barry Goldwater lost the 1964 presidential election by a landslide. Trump is reckoned to be a near-certain loser by the Republican establishment and they have been queuing up to endorse Cruz these last few weeks.

But Cruz believes in most of Trump’s zanier policy planks, plus the gold standard and is just as likely to lose.

Hillary Clinton has been the most likely democratic nominee for the last couple of years but is by no means unbeatable. Her election would be seen as perpetuating a political dynasty. She has some political baggage from her time as Secretary of State in Obama’s first administration and is regularly accused of being a plutocrat, too close to Wall Street.

If the Republicans had found a presentable middle-of-the-road candidate, they would have had a decent chance, according to the pundits. They have not managed to do this and look to be handing the White House to the Democrats once again.

Just as important, a Democratic victory in the presidential race could see the Republicans lose their majority in the House of Representatives since the winning presidential candidate tends to pull in party colleagues in the local races down for decision. All seats in the lower house are up for grabs every two years. In the six-year Senate cycle, 34 of the 100 seats will be contested, of which 24 are held by Republicans, so a bad presidential result could see their Senate majority (they hold 54 seats at present) up in smoke as well.

Given the prospect of a winnable presidential election and a decent chance of holding on to majorities in both legislative chambers, why has the Republican Party lumbered itself with apparently unelectable alternatives and a serious risk of losing on all fronts?

To some degree, this just reflects the very open system of presidential primaries: the candidate for both parties is chosen by registered supporters in each state, and not by the party managers in smoke-filled rooms. Trump did not require prior endorsements from party elders, or campaign money, since he has piles of it.

The middle-of-the-road candidates have all failed in the primaries and Cruz, the only surviving rival to Trump, looks equally unelectable, if possessed of better manners.

The registered Republican voters in the primaries are not representative of the broader electorate and Trump has been able to channel the anti-establishment anger of many voters. It has been a long recession and US real incomes are still stagnating even if the unemployment rate is down.

Either Trump or Cruz would promote policies likely to cause serious economic damage. Both are against further trade liberalisation and want to curb imports from China. Both want to restrict US companies from investing abroad. Both would pursue isolationist and inward-looking policies across the board, and wish to reduce American commitment to European security.

Keeping out immigrants is not exactly how the American economy got where it is today. As for returning the dollar to the gold standard, any attempt to do so would cause an instant world financial meltdown.

So it should not be too difficult for Hillary Clinton, the likely Democratic nominee, to defeat either of her two possible opponents. One despairing Republican strategist summed it up like this: “We have a choice: we can lose big with Cruz or lose ugly with Trump.”