Leading article: Newt Gingrich's second coming

The phoenix-like rebirth of Newt Gingrich underscores how strange is the battle for the 2012 Republican nomination. A few months ago, his campaign was written off for dead – yet suddenly he has taken a commanding lead over Mitt Romney, the long-accepted front runner, and at the perfect moment, with Iowa's caucuses just three weeks away. Americans are supposed to be up in arms against Washington – yet Mr Gingrich is the quintessential Washington insider, a lobbyist and public speaker and, of course, a former Speaker of the House of Representatives, who has parlayed his government expertise into a lucrative enterprise, "Newt Inc".

Republicans are united in a visceral desire to defeat Barack Obama – yet, after their flirtations with Michele Bachmann, Rick Perry and Herman Cain, they are turning to yet another candidate whom the polls suggest would be unable to achieve that. Nonetheless, the rise of Mr Gingrich should not be seen simply as the latest sign of the party's refusal to take to its heart Mr Romney, the potential opponent most feared by the White House. His flaws are well-known. But he is a remarkable politician, with the ability to take the fight to Mr Obama that his rivals cannot match.

Mr Gingrich is bombastic, hyperbolic and possessed of boundless self-regard. His career has been repeatedly marked by a lack of discipline, both professional and personal. He is intemperate, aggressive and often hypocritical: tellingly some of his sharpest critics are the very Republican lawmakers who worked with him during his heyday on Capitol Hill.

Yet, for ordinary Republicans, his virtues outweigh the flaws. These, showcased in every candidates' debate, include a fluency with the issues, and an ability to produce bold ideas; some new, some hare-brained, but some – such as his more humane approach to illegal immigration – with an acceptance of realities which escape most of his opponents. Mr Gingrich is a conservative, but one willing to admit that sometimes government can help solve problems. The standard wisdom is that he will over-reach and self-destruct, as so often in the past. But in this unconventional race, nothing is for sure.