Clinton, the New York senator, had the support of 40 percent of those surveyed compared to 20 percent for Obama, the Illinois senator, Marist College Institute for Public Opinion said.
Former North Carolina Sen.was third (12 percent) and New Mexico Gov. fourth (7 percent).
On the Republican side, former Massachusetts Gov.with 25 percent held a slight edge over former New York Mayor at 21 percent. Sen. of Arizona was third at 18 percent, and , the actor and former Tennessee senator, was fourth at 10 percent.
The New Hampshire primary, traditionally held in January, plays a key role in the presidential nomination process because it is one of the first tests of the candidates' popularity with voters. A strong showing in New Hampshire can provide momentum for candidates in the next round of primaries in larger states.
Voters in the primaries select delegates to their party's national presidential nominating convention who are pledged to different candidates.
Clinton was the overwhelming choice among those polled who want a strong leader or someone who will bring about change - 44 percent chose her compared with 20 percent for Obama and 11 percent for Edwards.
Clinton also drew the most support - 33 percent - from those questioned who ranked the Iraq war as their top issue. Clinton was seen as the most likely Democrat to win in November, getting the nod from 58 percent in the survey.
In the Republican field, when people were asked to pick a strong leader, Romney got 29 percent, compared with 23 percent for McCain and 22 percent for Giuliani.
Security against terrorism was the most important issue for Republican voters; on this issue, Romney was picked by 29 percent, and Giuliani and McCain by 21 percent each. Giuliani was picked by more people in the survey as having the best chance of winning in November - 36 percent versus 30 percent for Romney.
The poll, done by Marist College Institute for Public Opinion, was conducted from Oct. 4-9 and involved telephone interviews with 1,512 registered voters and New Hampshire residents likely to register in time to vote in the presidential primary. It has a margin of sampling error of plus or minus 4 percentage points for Democratic primary voters and 4.5 percentage points for Republican primary voters.
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