Americans are divided over the U.S.-led war in Afghanistan — a key voting issue in the 2008 presidential election — according to a FOX News poll released Monday.

President Obama's campaign was based largely on opposition to the Iraq war and support for a military strategy in Afghanistan. But just as Iraq has lost much of its political contentiousness, Afghanistan may be emerging — albeit to a lesser degree — as the “new” Iraq.

Americans are divided on both the Afghan war itself and on its expansion, according to the latest FOX News poll.

While a slim majority of Americans — 51 percent — say they approve of the job Obama is doing on Afghanistan, almost one-third disapprove (32 percent). Another 17 percent are unsure.

When voters are asked about their overall view of the war in Afghanistan, just about as many support it (46 percent), as oppose it (45 percent).

Click here to see the full poll results.

Members of the president’s own party oppose the war by a nearly two-to-one margin (62 percent to 33 percent), while Republicans support the conflict by a better than two-to-one margin (66 percent to 26 percent). Independent voter sentiment closely mirrors the overall results (47 percent support and 41 percent oppose).

When the question is shifted to a potential escalation of the Afghan war, overall opposition broadens. Asked how they feel about “sending additional U.S. troops” into the conflict, exactly half of Americans — 50 percent — say they oppose the idea, while 41 percent support it.

Party differences are once again stark, as Democrats oppose the escalation by a 62 percent to 30 percent margin, and Republicans support the troop increase by a 58 percent to 31 percent margin. Almost 6 in 10 independents (58 percent) oppose the idea.

Given the previous administration’s efforts to create a link between U.S. actions in the region and the fight against terrorism, it’s interesting to note how Americans view the Afghan war in this context. When U.S. military action in Afghanistan is posed as “necessary to protect Americans” from terrorist attacks at home, support jumps significantly — up to 58 percent. Among Republicans, support for the Afghan effort rises to almost three in four (73 percent) when posed this way. This suggests that if Obama is able to convincingly cast the war in these “homeland security” terms, he may generate greater public backing.

The national telephone poll was conducted for FOX News by Opinion Dynamics Corp. among 900 registered voters from September 15 to September 16, 2008. The poll has a 3-point margin of error.

Click here to see the raw data.

Ernie Paicopolos is a Principal at Opinion Dynamics Corporation