¡Estimados Republicanos!

In 2004, George W. Bush—an immigration-friendly Republican who spoke semi-passable Spanish—won re-election with about 40% of the Hispanic vote. This year, immigration hardliner Mitt Romney got about 27% of the Hispanic vote, according to the main exit poll—four points fewer than John McCain in 2008.

Had Mr. Romney matched Mr. Bush's Hispanic percentage, he could have netted an additional million votes or more, or nearly half of Barack Obama's popular margin on Tuesday. Those votes might have made a difference in states with large Hispanic populations such as New Mexico, Colorado, Nevada, Florida and even Virginia, all of which Mr. Bush won and Mr. Romney lost.

That's something broken-hearted GOP voters should ponder as they try to make sense of their defeat. There are plenty of reasons Mr. Romney came up short, and yes, Hispanics are not single-issue voters. But the antagonistic attitude that the GOP too often exhibits toward America's fastest-growing demographic group on immigration policy goes far to explain Tuesday's result.

Related Video

Hoover Institution research fellow Bill Whalen on whether Mitt Romney lost because Republicans have turned off minorities. Photos: Associated Press

It's also so unnecessary. Immigrants should be a natural GOP constituency. Newcomers to the U.S.—legal or illegal—tend to be aspiring people who believe in the dignity of work and self-sufficiency, and they are cultural conservatives. They are not the 47%. Republicans are also supposed to be the folks who have figured out the law of unintended consequences, such as that imposing ever-tighter border controls discourages the millions of illegal immigrants living in this country from returning home.

We have done our best over the years to explain such points, to which we would add that the free movement of labor is a central component of economic growth. Yet it has become near-orthodoxy among many conservatives to denounce every attempt at immigration reform as a form of "amnesty"—now as much a devil word on the right as "vouchers" are on the left.

Enlarge Image

Close

Associated Press

Volunteers for President Barack Obama's reelection campaign, Carissa Valdez, right, and Vanessa Trujillo, left, as they leave campaign headquarters as they work to register new voters while they canvass a heavily Latino neighborhood shopping plaza Friday, June 29, 2012, in Phoenix.

We understand the law-and-order issues at stake, particularly along the border, as well as questions of fairness in allowing illegals to jump the immigration queue. But the right response isn't mass deportation—as politically infeasible as it is morally repulsive. It's a rational, humane, bipartisan reform that broadens the avenues to legal immigration, both for those abroad and those already here.

Mr. Obama created a potentially fruitful opening to the GOP when he failed to do anything of the sort legislatively in his first term—a failure for which he was repeatedly scored in his September interview with Univision. A nimble GOP adversary might have seized the opportunity to present himself as the real immigration reformer.

But not Mr. Romney, who often pandered to his party's nativist wing (especially after Texas Governor Rick Perry entered the primaries), even endorsing what he called "self-deportation." That may have endeared him to one or two radio talk show hosts, but it proved a disaster on Tuesday.

And not only with Hispanics: Exit polls show that Asian-Americans went for the President over Mr. Romney by a whopping 73%-26%, an 11-point improvement over Mr. Obama's margin in 2008. How many other non-white groups can the GOP lose and still consider itself a national party?

No doubt this editorial will provoke letters denouncing us for being soft on the issue. Now is an opportune time to ask those disapproving readers how many more Tuesdays like this one they'd care to repeat?

A version of this article appeared November 8, 2012, on page A20 in the U.S. edition of The Wall Street Journal, with the headline: ¡Estimados Republicanos!.