New Hampshire ? Foreign policy blended with domestic issues Wednesday night at a two-hour campaign debate for Democrats in the nation’s first primary state.

Several of the Democrats endorsed payroll tax increases to assure a stable Social Security system. Health care, and the drive for universal coverage, also figured prominently in the debate.

A question about lowering the drinking age from 21 to 18 drew a cheer from the students listening in the Dartmouth auditorium. And expressions of support only from former Sen. Mike Gravel of Alaska and Rep. Dennis Kucinich of Ohio.

The opening question of the two-hour debate instantly plunged the eight contenders into the issue that has dominated all others – the war in Iraq.

The leading Democratic presidential hopefuls conceded they cannot guarantee to withdraw all U.S. combat troops from Iraq by 2013, the end of the next president’s first term.

“I think it’s hard to project four years from now,” said Sen. Barack Obama of Illinois.

“It is very difficult to know what we’re going to be inheriting,” added Sen. Hillary Rodham Clinton of New York.

“I cannot make that commitment,” said former Sen. John Edwards of North Carolina.

Sensing an opening, Sen. Christopher Dodd of Connecticut and New Mexico Gov. Bill Richardson provided the assurances the others would not.

“I’ll get the job done,” said Dodd, while Richardson said he would make sure the troops were home by the end of his first year in office.

The debate was broadcast on MSNBC.