United States:In a day of attacks and parries over the credentials of the Democratic candidates for president, Hillary Clinton belittled Barack Obama, John Edwards tweaked Ms Clinton and - in the oddest twist - US president George Bush praised the former first lady's experience.
On Tuesday, the Democratic race for president at last looked more like a shoving match than a civil airing of policy differences.
The volleys came as Mrs Clinton also began fighting back against Republican White House contenders who have tried to strengthen their standing among conservatives by airing television advertisements against her.
Facing a dip in her Iowa and New Hampshire poll ratings, Mrs Clinton responded with an advertisement saying the "old Republican attack machine is back", going after her because of her strength and experience.
Yet Mrs Clinton's assault against both Mr Obama and her Republican critics underscored the relative fragility of her status as the frontrunner for the Democratic nomination.
In Iowa, which kicks off the presidential races with its January 3rd caucuses, Mr Obama and Mrs Clinton are virtually tied in the polls. Mr Edwards, the former North Carolina senator, is close behind. Mrs Clinton's lead in New Hampshire has narrowed.
Most unusual was the intervention of Mr Bush. Calling Mrs Clinton a "very formidable candidate", the Republican president told ABC News: "There is no question that Senator Clinton understands pressure better than any of the candidates, you know, in the race."
Meanwhile, Mrs Clinton ridiculed Mr Obama for saying the day before that his strongest experience in foreign relations was living in Indonesia from the age of six to 10.
Mrs Clinton said that as a first lady and senator she had "met with countless world leaders and known them personally".
"Now voters will judge whether living in a foreign country at the age of 10 prepares one to face the big, complex international challenges the next president will face," she told a crowd in Shenandoah, Iowa.
Campaigning in the snowbound lakes region of central New Hampshire, Mr Obama responded by criticising Mrs Clinton's Senate vote to authorise the Iraq war. "I was wondering which world leader told her that we needed to invade Iraq, because that is the conventional thinking that we're going to have to break," Mr Obama said.
The Edwards campaign mocked Mrs Clinton for her remarks on Mr Obama's life in Indonesia. "Now we know what Senator Clinton meant when she talked about 'throwing mud' in the last debate," Mr Edwards's communications director, Chris Kofinis, said.
"Like so many other things, when it comes to mud, Hillary Clinton says one thing and throws another."
One Republican candidate, former New York mayor Rudolph Giuliani, took a swipe at Mrs Clinton in Chicago. "Senator Clinton has had so many different positions on Iraq, I would not want to be the one to state her most current position, because I'd probably get it wrong," he said, adding that Mr Obama, by contrast, has stood "clearly against the war".
Meanwhile, the former Arkansas governor Mike Huckabee, buoyed by strong support from Christian conservatives, has surged past three of his better-known rivals and is now challenging former Massachusetts governor Mitt Romney for the lead in the Iowa Republican caucuses, according to a new poll.
Mr Huckabee has tripled his support in Iowa since late July, eclipsing Mr Giuliani, former senator Fred Thompson of Tennessee and senator John McCain of Arizona.
Mr Huckabee now runs almost evenly with Mr Romney, the longtime Iowa frontrunner.
Mr Huckabee's rise from dark horse to contender in Iowa is one more unexpected twist in a race that has remained fluid throughout the year and adds another unpredictable element to the competition for the Republican nomination.
Still, there are other signs in the poll suggesting that Mr Romney remains the candidate to beat in the state and that gains for Mr Huckabee may be harder to achieve in the next 41 days than they were over the past four months.
Mr Romney outperforms Mr Huckabee and other Republicans on key attributes, with two notable exceptions - perceptions of which candidate best understands people's problems and which candidate is the most honest and trustworthy. On both, they are tied. At the same time, Iowa Republicans see the former Arkansas governor as less credible than Mr Romney, Mr Giuliani or Mr McCain on some top issues.
Mr Huckabee's gains were concentrated among the party's conservative core. He saw a 28 percentage point jump in support from evangelical Protestants, to 44 per cent, and a 19 point rise among conservatives, to 30 per cent.
But despite these advantages, Mr Huckabee's support comes almost exclusively from certain voters. His challenge will be to expand his appeal. Almost seven in 10 of those who back him are evangelical Protestants. Mr Romney, by contrast, has more broadly-based support. - (LA Times-Washington Post service)