The referendum on May 5, 2011, will ask the public whether they want to change voting in elections from the traditional first-past-the-post system (FPTP) to proportional representation, or the alternative vote system (AV).
The Rev George Hargreaves, leader of the Christian Party, said: “AV proportional representation could be the mechanism that the Christian Party need for electoral breakthrough.
“The Christian Party has suffered from the fear of Christian voters that their vote will be wasted if they vote for us, despite sharing our beliefs and conviction that a specific Christian party presence is needed in Westminster.
“The Alternative Vote system, if properly understood, provides an insurance policy that will deal with this problem."
The referendum was one of the conditions put forward by the Lib Dems when they agreed to enter into a coalition government with the Tories.
It is unpopular with many Conservatives who believe any change to the rules will increase the likelihood of elections resulting in hung parliaments and coalition governments, while the FPTP system typically delivers a clear winner.
Prime Minister David Cameron is opposed to any change but is unlikely to lead the No campaign, while Lib Dem leader Nick Clegg is likely to lead the charge for the Yes vote.
It will be the first referendum held in Britain since the public voted to stay in the Common Market in 1975.