US Democrat and Republican presidential candidates are squaring up for debates in New Hampshire, three days before primary polls in the north-east state.
Six Republicans and four Democrats are taking part in the debates, after the organisers excluded weaker candidates.
The Democrat debate marks the first face-to-face clash between frontrunners Hillary Clinton and Barack Obama since Mr Obama's Iowa victory on Thursday.
Latest polls suggest that Mrs Clinton's lead in New Hampshire may be shrinking.
A Reuters/C-Span/Zogby poll on Saturday gave Mrs Clinton 32% to Senator Obama's 28%.
Among Republicans, former Massachusetts governor Mitt Romney was closing the gap on veteran Arizona Senator John McCain, who has long led polls in the state.
Mr Obama - a 46-year-old first-term senator from Illinois who aims to become the first US black president - and Republican Mike Huckabee emerged victorious in the Iowa caucuses in the first contest of the 2008 election.
Iowa and New Hampshire may not necessarily produce a winner from either campaign, but could boost contenders' chances ahead of primaries in larger states.
A Republican primary is being held in Wyoming on Saturday.
Both debates in New Hampshire are being organised and broadcast by ABC television.
The Republican debate is to be held first, with Mr Romney hoping to boost his campaign after coming a disappointing second in Iowa to Mr Huckabee.
They are joined by former New York Mayor Rudy Giuliani, who is focusing his campaign on larger states which vote later in the campaign, anti-war candidate Ron Paul, actor and former Senator Fred Thompson and Senator John McCain.
The field for the Democratic debate was reduced when Senators Joe Biden and Chris Dodd pulled out of the campaign after a poor showing in Iowa.
Two others, Dennis Kucinich and Mike Gravel, were excluded because they failed to finish in the top four in Iowa and have consistently polled below 5% in New Hampshire and national polls.
Mrs Clinton and Mr Obama will be joined by John Edwards, who came second in Iowa, and New Mexico Governor Bill Richardson.
Mr Obama has drawn crowds in New Hampshire with a message of change, but Mrs Clinton is hoping to make up for a disappointing third place in Iowa and re-establish herself as the leading Democrat.
The parties will not formally select their candidates until their presidential conventions in August and September, although the nominees are likely to be determined well before then.
The eventual winner will replace President George W Bush, who is constitutionally barred from seeking a third term.
Analysts say the 2008 campaign is the most open race in more than 50 years, with no sitting president or vice president seeking their party's nomination. ( BBC )