Democratic Sen. Barack Obama has edged ahead of rival Hillary Clinton in New Hampshire less than a month before the state's nominating primary in the 2008 race for the White House, a new poll showed.

The Concord Monitor newspaper poll showed the U.S. senator from Illinois leading Clinton 32 percent to 31 percent in New Hampshire, which on Jan. 8 holds the first primary in the run-up to the November 2008 presidential election. The survey had a 4 percentage point error margin.

It mirrors other polls this week showing the New York senator's lead vanishing in New Hampshire, suggesting a fiercely competitive race in a state where the former first lady led by a comfortable margin just weeks ago.

On Wednesday, a WMUR-TV/CNN poll showed the race a statistical dead heat with Clinton leading Obama 31 percent to 30 percent. In September, Clinton enjoyed a commanding lead of more than 20 points over Obama.

New Hampshire's primary helps kick off the state-by-state battle to pick candidates for the Nov. 8, 2008, election. The midwestern state of Iowa holds the first contest of the party nominating process with its Jan. 3 caucuses.

The Monitor said much of Obama's backing comes from undeclared voters while registered Democrats gave the most support to Clinton.

New Hampshire allows independents -- not just registered Republicans and Democrats -- to vote in its primary and they can choose either a Republican or a Democratic ballot.

Among Republicans, former Massachusetts Gov. Mitt Romney leads his Republican rivals in New Hampshire with 31 percent support, followed by former New York Mayor Rudy Giuliani at 18 percent and Arizona Sen. John McCain at 17 percent.