As with all charity activities it is important that charities maintain adequate books and records of their political activities.  Such books and records should be maintained in Canada and preferably in either English or French.

Here is an excerpt from CRA Guidance on Political Activities – CPS-022

“12. What records should a charity keep?
An organization that is involved in political activities will be expected to identify any expenditures made on such activities in order to demonstrate that substantially all of its resources have been devoted to charitable activities.
Where expenditures relate in part to political activities and in part to other activities, a reasonable allocation should be made and the methodology should be consistent from year to year. Where substantially all (90 % or more) of an expense is for charitable activities, then the whole expense should be considered a charitable expense. Similarly, if the expense relates substantially to a political activity, the whole expense should be counted as a political expense. In addition to its financial resources, any physical and human resources must be devoted substantially to its charitable purposes and activities.
A charity should choose record-keeping methods suited to its operations provided that the method chosen is consistently applied, complies with the requirements of the Act, and is sufficient to disclose its position.”

For more information on allocation see CRA’s Guidance on Fundrasing which has a schedule on allocating costs between different types of activities.

Here is a link to CRA Guidance on Political Activities – CPS-022 http://www.cra-arc.gc.ca/chrts-gvng/chrts/plcy/cps/cps-022-eng.html

As well here is a copy in PDF of the CRA Policy Statement on Political Activities by Canadian Charities CPS-022 – September 2, 2003 so that you can download it easily to your computer.