Cokie Roberts and Steven V. Roberts

TRUMP'S 'DREAMMMM' OPPONENT

We talked recently to a senior Republican who has devoted his career to conservative candidates and principles. Who would he vote for, given a choice between Donald Trump and Hillary Clinton?

Clinton, he answered immediately. Trump would "blow up" everything this man had spent his life building.

A few days earlier, we'd interviewed a seasoned Republican strategist from Pennsylvania. With Trump and Sen. Ted Cruz leading the GOP race, she lamented, "My party's leaving me."

As the Republican party veers rightward, as Trump and Cruz continue to dominate the polls, as pragmatists like Jeb Bush and John Kasich continue to falter, the GOP is handing the Democrats an enormous present. They are abandoning the moderate center of American politics.

As a result, they are giving the Democrats a golden opportunity to accomplish something that's happened only once since Harry Truman's victory in 1948: the same party winning the White House for a third straight election. (George Bush 41, succeeding Ronald Reagan in 1988, was the only one since Truman to accomplish that feat.)

But the Democrats are fully capable of blowing their chance. Many times over the last half-century, they have fallen prey to what might be called The Great Liberal Delusion. And it could be happening again.

The latest polls in Iowa and New Hampshire show Sen. Bernie Sanders, a self-described socialist, posing a serious challenge to the Democratic front-runner, Hillary Clinton. And she's worried enough to start attacking her rival by name.

Clinton should still win. She has a better national organization and a huge advantage among minority voters. But if Sanders should somehow capture the nomination, the Democrats would give back the gift the Republicans are offering.

"I want to run against Bernie," Trump told a New Hampshire rally this week. "That's my dream. My dreammmm."

Many smart Republicans worry that Trump or Cruz would be another Barry Goldwater, who won just six states and 38.5 percent of the vote in 1964. But on the flip side, Sanders could be another George McGovern, who played to large, adoring crowds on college campuses in 1972 -- and won exactly one state.

Yes, a lot has changed since those elections. New technologies enable candidates to disregard elite party structures and communicate directly with supporters. Anger and alienation, fueled by stagnating wages and menacing terrorists, are generating support for insurgent candidates and extreme remedies.

But the basic rules of politics have not been repealed. The center of gravity in this country still sits in the moderate middle, with a slight tilt to the right.

In exit polls during the 2012 election, 41 percent called themselves moderates, with 35 percent identifying as conservatives and 25 percent as liberals. A Gallup poll a year ago produced similar results, with 24 percent choosing the liberal label. Only 6 percent said they were "very liberal," a fair description of Sanders' philosophy.

Then there's history. Between 1968 and 2008, Democrats won only three of 10 elections, and their only successful candidates were two moderate Southern governors: Jimmy Carter and Bill Clinton. Barack Obama could plausibly qualify as a liberal, but his victories were as much about personality as philosophy. The other left-leaning nominees -- McGovern, Hubert Humphrey, Walter Mondale and Michael Dukakis -- all lost decisively.

Give Sanders credit. He's run a good campaign bristling with energy and excitement. He's capitalized effectively on the left's resentment of income inequality and its long-standing disdain for the Clintons as moderate heretics.

He's also revealed Hillary's weaknesses as a candidate. She's never been in her husband's class as a retail campaigner. Her unfavorable ratings consistently hover around 50 percent, and a majority views her as dishonest and untrustworthy.

But with all that baggage, she's still far more electable than Sanders. She has a much better chance of appealing to disillusioned Republicans, and her historic attempt to become the first female president should compensate for some of her personal shortcomings.

Sanders, don't forget, would be 75 on Election Day -- almost six years older than Reagan, our oldest president so far. And his policy proposals range far outside the American mainstream.

The Wall Street Journal added them all up and produced a price tag of $18 trillion, with most of that going to a government-run health care system. Washington's share of the gross national product would rise from about 20 percent to 30 percent -- a figure reached only once before, at the height of the military build-up during World War II. Taxes would skyrocket.

No wonder Sanders is Trump's "dreammmm" opponent.

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