Reuters - A Taliban rocket struck the grounds of Afghanistan's presidential palace on Tuesday, just two days before incumbent Hamid Karzai seeks re-election in tense polls that could go to a second round.
Not only is Karzai fighting for a fresh mandate, but the election is also a test of U.S. President Barack Obama's strategy of escalating the 8-year-old conflict in an effort to reverse recent Taliban gains.
In a speech on Monday aimed at bolstering public support, Obama called the Afghan conflict "a war worth fighting".
Election campaigning officially ended at midnight after a final day that saw hectic rallies in support of Karzai and his main rival, former foreign minister Abdullah Abdullah.
Polls show Karzai likely to win Thursday's vote, but not with the outright majority required to avoid a second round. He is relying on the last-minute support of former guerrilla chieftains in a bid to tip the balance.
His main rival Abdullah, an urbane eye doctor, has run an energetic campaign, seeking to garner support from beyond his base in the mainly ethnic-Tajik north.
Several small rockets were fired overnight and a police source said one caused some damage inside the sprawling, fortified presidential palace compound in central Kabul, while a second hit the capital's police headquarters. Neither caused any casualties.
Militants who have vowed to disrupt Thursday's election have fired rockets at the capital twice this month as well as detonated a massive suicide bomb outside the NATO-led International Security Force Headquarters (ISAF) in central Kabul that killed seven people and wounded dozens more.
Such attacks have been rare in the capital this year.
Taliban spokesman Zabihullah Mujahid, in a message sent to Reuters via mobile phone, claimed the fighters had fired four rockets, but gave no further details.
Recent polls give Karzai about 45 percent of the vote to 25 percent for Abdullah. Since the polls were conducted, Karzai has secured the last-minute endorsements of some former militia chieftains, hoping they help secure a first round victory.
Karzai's reliance on the ex-militia leaders has raised alarm among his international backers worried that warlords could return to power in the country they dominated for decades.
General Abdul Rashid Dostum, an Uzbek militia leader who won 10 percent of the vote in 2004, returned to the country from exile in Turkey and held a huge pro-Karzai rally in his northern home city of Shiberghen on Monday.
The United States and the United Nations both expressed concern that Dostum could return to government. Washington said he may have been responsible for human rights violations.
Karzai's two vice presidential running mates are also former militia chiefs, from the Tajik and Hazara minorities. Last week he received the public endorsement of Ismail Khan, a former militia leader in the western city of Herat.
Taliban disruption could hurt Karzai's chance of a first-round win by lowering turnout in southern areas most affected by the insurgency, heartland of the Karzai's support.
More than 30,000 extra U.S. troops have arrived in Afghanistan this year, raising the total number of Western troops above 100,000 for the first time, including 62,000 Americans.
The Western troops will maintain outer perimeter security during the election, with Afghan soldiers and police guarding towns and polling stations. The NATO-led Western force said on Tuesday it would refrain from conducting offensive operations on election day, in line with an earlier pledge from Afghan troops.
If Karzai fails to secure victory in a first round, he would most likely face Abdullah in a second round in early October.