Six men have been jailed for more than 13 years in total over election fraud in a council vote.
Police started investigating after reports Labour councillor Lydia Simmons lost her Slough Central ward seat to Tory Raja Khan following corrupt practices in May 2007.
Raja Khan, along with two others, had previously admitted the offences. Three other men were convicted by a jury.
Reading Crown Court heard they created hundreds of false names in the weeks running up to the local election and entered them on the voter register.
It became Thames Valley Police's largest ever election fraud investigation ending with the men, all from Slough, sentenced on Friday at Reading Crown Court.
Raja Khan, 52, admitted conspiracy to defraud the returning officer and perjury and was sentenced to three-and-a-half years in jail.
Mohammed Basharat Khan, 46, pleaded guilty to conspiracy to defraud the returning officer and conspiracy to pervert the course of justice. He was jailed for three years and four months.
Mahboob Khan, 46, was jailed for four-and-a-half years after he was found guilty of conspiracy to defraud, conspiracy to pervert the course of justice and perjury.
Arshad Mahmood Raja, 53, was found guilty of conspiracy to defraud the returning officer. He was jailed for one-and-a-half years. Altaf Khan, 31, was found guilty of personation and was sentenced to four months. Gul Nawaz Khan, 57, pleaded guilty to perjury and was jailed for eight months.
Det Supt David Poole, senior investigating officer, said: "An election is arguably the most important event in a democracy and I would like to reassure the voting public that we will investigate and deal with any allegations of fraud in the run up to, or on, election day itself."
