Bush sought to encourage a high turnout at the polls despite the mounting insurgent carnage in the country.
"We're having elections on January 30. It is a historical moment," Bush told reporters at the White House.
"I know it's hard for a reason, and the reason is that there is a handful of folks that fear freedom," he said.
Bush described 14 of Iraq's 18 provinces as "relatively calm" and added that in some "the terrorists are trying to stop people from voting."
According to an internal State Department poll, only 32 percent of Sunnis are "very likely" to vote and 88 percent said they would stay away from the polls if they feared attacks.
A US official said the findings were "not surprising" but said efforts would continue to encourage the participation of Sunnis, who enjoyed power until US troops toppled Saddam Hussein's regime in 2003.
Amid increasing unrest, US Defence Secretary Donald Rumsfeld is sending a retired general to Iraq to evaluate the development of Iraqi security forces, a centrepiece of the US strategy to defeat a growing insurgency, a Pentagon spokesman said on Friday.
The mission, first reported by The New York Times, reflected the administration's deepening concern over the situation in Iraq where insurgents are mounting an intensifying campaign to derail January 30 elections.
The Times said retired General Gary Luck's review will be "open ended" and include a broader look at US military operations, including US troop levels and the strategy for fighting the insurgency.
In the latest attack against US forces, a bomb tore apart an armoured fighting vehicle in Baghdad on Thursday, killing seven US soldiers, while two marines died in the volatile western province of al-Anbar.
It was the largest number of US troops killed in a single attack since last month's suicide bombing in a military mess hall at a Mosul base that killed 22 people, including 14 US service members.
In Texas, US Specialist Charles Graner was to go on trial by court-martial facing a maximum sentence of more than 20 years in prison if found guilty on charges emanating from the sexual, physical and psychological abuse of prisoners at the Abu Ghraib jail near Baghdad.
His trial at the Fort Hood army base will be the first court martial in the Abu Ghraib scandal to be held in the United States.
Graner, 36, has pleaded not guilty to the charges, which stem from incidents that allegedly took place between October and December 2003, stirring a global outcry and deeply embarrassing the US military.
Meanwhile, French President Jacques Chirac said he was "worried" about the fate of 43-year-old Florence Aubenas, a senior correspondent for the French daily Liberation missing in Iraq, and warned journalists to stay out of the country.
Aubenas, 43, and Hussein Hanun al-Saadi left their Baghdad hotel early Wednesday and have not been seen since.
In the restive town of Samarra north of Baghdad, two Iraqi soldiers and a civilian were killed in clashes with armed insurgents, while an Iraqi security officer in Kut, south of Baghdad, was killed overnight by gunmen.