On the eve of the second key battle in the US presidential nomination race, Democratic Sen. Barack Obama and Republican Sen. John McCain led in most of the polls. 

However, in the New Hampshire primary, both parties' races are still too close to call, US News and World Report said Monday. 

On the Democratic side, Obama (D-IL) is winning in 8 of 10 surveys over Sen. Hillary Clinton (D-NY). 

Similarly, John McCain (R-Ariz.) holds a lead in 8 of the 10 surveys over Mitt Romney, the former Republican governor of Massachusetts, who is leading in the other two surveys. 

Former Sen. John Edwards (D-NC) continues to draw about one-fifth of Democratic support, while among Republicans, former mayor of New York Rudy Giuliani, Rep. Ron Paul, and (D-TX) as well as former governor of Arkansas Mike Huckabee are clustered together at around 10 percent each. 

The New Hampshire Union Leader, a local newspaper, said Tuesday the polls are "yo-yoing" as Tuesday's vote nears, offering the "chance of a photo finish" on both sides. 

USA Today says the "phenomenal rise" of Obama and the resurgence of McCain have made the contests too close for comfort for former frontrunners Clinton and Romney. 

The AP says the "wide open and intense" Republican race "has gotten ever tighter." 

An American Research Group poll conducted January 5-6 has Obama at 39 percent, Clinton 28 percent, John Edwards 22 percent. 

Among 600 likely Republican voters, McCain is at 35 percent, Romney 27 percent, Mike Huckabee 12 percent, Rudy Giuliani 10 percent. 

A CNN /WMUR poll has Obama at 39 percent, followed by Clinton, 29 percent, Edwards, 16 percent. 

Among Republican voters, McCain leads with 32 percent, followed by Romney, 26 percent; Huckabee, 14 percent. 

A Rasmussen poll of January 4-5 has Obama at 39 percent, followed by Clinton, 27 percent; Edwards, 18 percent. 

A USA Today/Gallup poll of 778 likely Democratic voters conducted January 4-6 has Obama at 41 percent, followed by Clinton,28 percent; Edwards, 19 percent.

On Republican side, McCain is at 34 percent; Romney, 30 percent; Huckabee, 13 percent. 

In the quadrennial US presidential election year, the two parties officially nominate their respective candidate for presidency at their national conventions, usually held in the summer before the election in November. 

The nomination is determined by the state-by-state primary elections held between January and June in the election year. 

The first-in-the-nation caucus in Iowa on Jan. 3 and the first-in-the-nation primary in New Hampshire on Jan. 8 are considered as the winnower or the weather vane for the presidential nomination process. 

(Xinhua News Agency January 8, 2008)