Tom Tancredo, the immigration-crazed congressman from Colorado, is never going to be the Republican nominee for president. But Wednesday’s night’s CNN/YouTube debate confirmed that he has prevailed in the contest of ideas — if raw xenophobia can be called an idea.

For much of the first stretch of what should have been a critical debate for candidates who are racing toward Iowa caucuses that are now just six weeks away, the Republicans who would be president stumbled over one another to out-Tancredo Tancredo. And, while they did not quite rival the congressman’s rabid rhetoric, the other contenders made it clear that they can be just as crudely aggressive as the Coloradan when it comes to rejecting the Biblical injunction to welcome the stranger.

After former Massachusetts Governor Mitt Romney tore into Rudy Giuliani for being insufficiently hateful toward immigrants during his time as mayor of New York, Giuliani ripped Romney for employing undocumented workers in his home.

The two leading Republican contenders, who were standing next to one another on the stage in St. Petersburg, Florida, raised their voices to levels rarely heard in presidential debates as Giuliani accused Romney of operating a “sanctuary mansion.”

Noting that during Romney’s tenure as governor six Massachusetts cities had committed to treat immigrants with respect and sensitivity — identifying themselves as “sanctuary cities” — Giuliani growled, “In his case, there were six sanctuary cities. He did nothing about them. There was a sanctuary mansion — at his own home, illegal immigrants were being employed.”

Romney angrily denied the allegation before attacking the candidate who actually poses a bigger threat — at least in Iowa — to his tenuous front-runner status, former Arkansas Governor Mike Huckabee, for being soft on children.

Huckabee, who is now essentially tied with Romney among likely Iowa caucus goers, allowed as how it was reasonable to provide education to the children of undocumented immigrants — on the theory that children ought not suffer because of the status of their parents.

That might be a position that George W. Bush would respect, but Romney was having none of it. Insisting that giving the children of immigrants equal access to education amounted to “preferential treatment,” Romney sneered at Huckabee, “Mike, that’s not your money, that’s the taxpayers’ money. Illegals are not going to get better breaks than our own citizens.”

Of course, equal access to education is not a “better break” for anyone. But logic is not required at a Republican debate where immigrant-bashing is on the agenda.

Indeed, it fell to the Tancredo to offer the most reasonable assessment of the evening.

The most explicitly anti-immigrant candidate for the presidency since the demise of the Know-Nothing Party observed that the other — supposedly more credible — Republican contenders were attempting to “out-Tancredo” him.

On this point, there could be no debate.