Newt Gingrich speaks at Tommy’s Ham House, in Greenville, South Carolina, November 30, 2011 (AP Photo/Richard Shiro, File)

It figured that a Republican presidential primary race defined by nothing so much as a taste for cruel and unusual politics would eventually see Newt Gingrich emerge as the cruelest and most unusual contender. Sure, Michele Bachmann, Rick Perry and Herman Cain might strive for the lowest common denominator. But Gingrich would outdo them in that department, despite heroic feats of insanity, stupidity and sex scandals by the other three. And so he has, emerging as the default choice of a new breed of Republican so extreme it would scare the bejeezus out of Barry Goldwater or Ronald Reagan.

In the same week that saw the former Speaker of the House become the most serious challenger to Mitt Romney, the Republican very few Republicans seem to like, Gingrich showed his true colors. As part of the ongoing GOP rant against organized labor, he stepped up with a proposal to fire school janitors and replace them with child laborers. Blaming “the core policies of protecting unionization and bureaucratization” for “crippling” children, Gingrich told a Harvard audience, “It is tragic what we do in the poorest neighborhoods, entrapping children in, first of all, in child laws, which are truly stupid.” Gingrich did not misspeak. He was serious in suggesting that “most of these schools ought to get rid of the unionized janitors, have one master janitor and pay local students to take care of the school.”

Even in a party where shamelessness is now considered a virtue, it’s unsettling that a man who collected $30,000 a month for an hour of counsel to Freddie Mac administrators would attack school janitors, who according to the Bureau of Labor Statistics earn a mean wage of $13.74 an hour, or $28,570 a year. In response to Gingrich, the American Federation of State, County and Municipal Employees said, “The people you want to fire and replace with kids? A lot of them are parents. That job puts a roof over kids’ heads, food on the table, and provides them with healthcare and the chance to get an education. That job is the only thing between a kid and poverty.” But Gingrich has never been bothered by the human costs of right-wing social experimentation. So why start, now that the Grand Old Party seems to be longing for a return to the Gilded Age? Gingrich is betting there’s no such thing as going too far to the right in this race. He may be right; just days after he championed child labor, he secured the endorsement of New Hampshire’s Union Leader, a rigid-right newspaper determined to stop Romney.

It’s still hard to imagine that Gingrich, with all his personal and political peccadilloes, will win the nomination. Romney has plenty of his own money, along with a shadowy network of PACs that will profit from the Supreme Court’s dismantling of laws controlling corporate and personal campaign giving. That cash advantage will allow Romney to launch the electoral equivalent of a nuclear strike against the latest anyone-but-Mitt boomlet. But should GOP disdain for Romney be so overarching that Gingrich prevails, he will then be the beneficiary of the largesse that Karl Rove, the Koch brothers and others are accumulating to pay for an anyone-but-Obama campaign in the fall.

Looming over Newt’s nastiness and Mitt’s mediocrity is this “silent candidate”: the flood of corporate and Wall Street money that will pour into the election. It might be hard to take the other candidates seriously, but the threat posed to our democracy by this one should not be underestimated.