Polls in Cambodia opened today amid criticism of a crackdown against his dissenters by long-serving Prime Minister Hun Sen, who is set to hold on to power after nearly 33 years in office.  ''<div><br />''</div>''<div>The general election is the country's sixth since 1993 when it emerged from decades of war marked by death and destruction at the hands of Pol Pot's genocidal regime.</div>''<div></div>''<div>Critics say the election marks the decimation of democracy in the southeast Asian country following months of intimidation by the ruling party Cambodian People's Party and the dissolution last year of the main opposition Cambodia National Rescue Party.</div>