Rick Santorum, Newt Gingrich and the rest of Mitt Romney’s pursuers still have time to stop his rise in the race for the Republican presidential nomination. But not much. And not all of them.

Romney’s first-place finish in the Iowa caucuses, even if by only eight votes, erased the embarrassment of four years ago when he spent millions and finished a distant second to former Arkansas Governor Mike Huckabee. Now he leads in the polls in New Hampshire, where the 2008 primary winner, Arizona Sen. John McCain, is supporting him.

A victory tomorrow in New Hampshire would make the former Massachusetts governor the first Republican to win both the lead-off caucuses and first-in-the-nation primary in a contested campaign.

A Romney victory on 21 January in South Carolina, a state with a deeply conservative, evangelical-heavy Republican primary electorate, probably would assure his nomination at the Republican national convention in Tampa, Florida, this summer.

Which is why Gingrich hopes to create impossibly high expectations for Romney in New Hampshire — how else to try to take the shine off what is expected to be a comfortable victory?

Noting that Romney’s winning percentage in Iowa was an unremarkable one-quarter of the vote, Gingrich envisioned a day when the race would “eventually come down to one conservative and Gov. Romney, and he’ll continue to get 25%. By definition, at some point in that game somebody is going to start getting a lot more votes than Gov. Romney.”

Perhaps.

But for now, Gingrich, Santorum, Texas Governor Rick Perry, Texas Rep. Ron Paul and former Utah Governor Jon Huntsman all have visions of being the sole survivor of the competition to emerge as Romney’s chief rival, thereby postponing the day it happens, perhaps until it no longer matters.

The calculation that New Hampshire is exceedingly friendly terrain for Romney also accounts for the decision by Santorum, the former Pennsylvania senator, to send most if not all of his new, post-Iowa harvest of campaign donations straight to South Carolina for television commercials. It is also why Perry intends to try and resurrect his candidacy there.

The New Hampshire campaign is well under way, and going into back-to-back debates Saturday night and Sunday morning, has proved to be a fairly genteel one.

If experience is a guide, that won’t be true in the first-in-the South battleground this week.

“Things tend to get nasty down here in South Carolina,” said Wes Donehue, a consultant who worked for Minnesota Rep. Michele Bachmann before she dropped out of the race.

McCain, as much as anyone, knows all about that.

A dozen years ago, when McCain ran against George W. Bush, false rumours swirled continuously that his wife was a drug user, that one of the couple’s daughters was illegitimate and that he had committed treason while in a North Vietnamese prisoner of war camp.

McCain lost the primary, and the nomination along with it.

In 2008, the victory he won in South Carolina sent him on the way to the nomination. “It took us a while, but what’s eight years among friends?” he said jubilantly that night as he outdistanced Huckabee, Romney and others.

In fact, no Republican in more than 30 years has captured the party’s nomination without a victory in South Carolina.

Given the stakes, questions about Romney’s Mormon religion, his one-time support of abortion rights and other positions he once took as a governor of Massachusetts are to be expected.