Newt Gingrich is back in contention for the Republican presidential nomination partly because he understands the power of words, the pervasiveness of amnesia, and the dark art of making them work together.

It’s still hard to imagine Gingrich as president. He’s likely to blow himself up before next November. But the scary thing for Democrats is that Gingrich grasps these subtextual forces better than they do. It makes him a less predictable and possibly more dangerous opponent than Mitt Romney in the general election.

Gingrich helped Republicans seize control of the House of Representatives in 1994 with the help of “key words” tested by pollster Frank Luntz, who designed the “Contract with America.”

In 1990, Gingrich’s political action committee, GOPAC, put out an audio cassette with advice for Republican candidates. Gingrich followed up with a famous memo to Republicans called “Language: A Key Mechanism of Control”:

“As the tapes have been used in training sessions across the country and mailed to candidates we have heard a plaintive plea: ‘I wish I could speak like Newt.’ That takes years of practice. But, we believe that you could have a significant impact on your campaign and the way you communicate if we help a little.”

Gingrich’s list of “Optimistic, Positive Governing Words” included “common sense,” “courage,” “liberty,” “strength” and “vision.”

The list of what the congressman called “Contrasting Words” included “bosses,” “greed,” “lie,” “pathetic” and, of course, “taxes.”

The party internalized Gingrich’s message and for two decades has run linguistic circles around Democrats, turning inheritance taxes into “death taxes” and efforts to advise seniors on living wills into “death panels.” When it comes to demonizing the other side, nothing works like the Grim Reaper.

As critic and law professor Stanley Fish has pointed out, Republicans are also expert at stealing phrases like “individual rights” and “color blind” from the civil-rights movement and using them to win arguments on racial issues.

I’m not suggesting that Democrats ape the Republicans’ Orwellian approach and begin twisting words to imply the opposite of the truth, as Karl Rove did this week with an ad making it seem as if Elizabeth Warren favored bank bailouts that hurt the middle class. But the president could bring up his language game.

At a recent Bloomberg View lunch with David Axelrod of the Obama campaign, a group of journalists got a glimpse of the yawning language gap between the parties.

Hendrik Hertzberg of the New Yorker pointed out that it was a Democrat in the Carter administration, Donna Shalala, who in 1979 first began calling Social Security and Medicare “entitlements” instead of “insurance,” the term favored by President Franklin D. Roosevelt. Talk about a self-inflicted wound for Democrats. For all the years since, these programs have sounded like something for spoiled seniors.

When asked why the Obama administration continued to use the word, Axelrod didn’t have an answer. Nor could he explain why Democrats keep using the arid and unconvincing word “infrastructure.”