Only 35 percent of the voters support his "surge" of extra troops into Iraq--mainly conservatives, Greenberg says.
"He's lost the country on that," largely because Bush's credibility is so low, Greenberg adds. "Now it's all about the base."
Greenberg says, "Republicans are walking the plank for the president on Iraq. This will make them exposed and vulnerable" in 2008. But the situation also presents difficult challenges for the Democrats.
"Americans want the troops out, but they are also concerned about the consequences of withdrawal," such as the possibility that Iraq would descend further into chaos. "People don't like any of the alternatives," Greenberg says. "But if we are still in Iraq on Election Day 2008, it will be a very big win for the Democrats, a tsunami."
By Kenneth T. Walsh