Research: Voters lists on Ancestry.ca
After the arrival of the new collection at Ancestry.ca, here are the first results of me researching my Comeau family:
Before 1935, municipal voters lists were used in federal elections. Starting with the election of 1935, federal voters lists were created.
I searched for my great grandfather, Dosithée Comeau (1883- 1966) .
The first time he appears is on the 1940 list in Lachine, Québec, electoral district Jacques-Cartier:

He lived at 11, 6th avenue. His occupation is labourer. His daughter Béatrice (23 years old) is also listed. His first wife died in 1934:

In 1945, he is also listed in Lachine, this time at the address 17, 6th avenue (still listed as a labourer). His second spouse his now listed (the wedding took place on December 8th, 1942 in Lachine). His son Bruno (23 years old) joins Béatrice on the list:

Next, the 1949 Canada voters list. His address is 23, 6th avenue (still a labourer):

In 1957, still in Lachine at the same address, but now listed as a pensioner. I notice now that three other persons are listed at the address Probably renting rooms as it was common at that time:

In 1962, I cannot find Dosithée, as the address does not appear on the list:

Dosithée died on April 8, 1966 in Lachine.
The hurdles that were encountered during the search
The first difficulty was the index.
In 1940, the indexed name of my ancestor is Dosithie Comeau
In 1945, Doslthte Comeau
In 1949, Doeithee Comeau
And in 1957, Dosithae Comeau
I don’t understand why we see these differences as the page were generated by a typewriter and all the pages visited were clear and easily readable.
The second difficulty was the constant changes in electoral districts, making a narrow search harder:
In 1940, Lachine is under the electoral district of Jacques-Cartier
In 1945, Mont-Royal
In 1949, back to Jacques-Cartier
And in 1957, Jacques-Cartier-Lasalle
To help with this issue, you can visit the federal governement website, adn use the search page for the history of federal ridings:
http://www.parl.gc.ca/About/Parliament/FederalRidingsHistory/hfer.asp?byElection=&canName=&canParty=0&Election=N&genElection=&rid=&ridName=&ridProvince=&Search=T&Source=AboutParl_Process&txtComments=&Language=E
Some tips
Always remember about possible ways or writing a name or surname. I saw some Comeau, Commeau, Como and Macameau listed.
If a person cannot be found, look for known neighbors. That was how I saw that the known address of my ancestor was not listed in 1962.
Resources
http://www.collectionscanada.gc.ca/022/022-911.006-e.html
http://www.ancestry.ca/cavoterslists