Mr Singh, heading the party's farmer cell, cited the recent statement of the Archbishop of Gandhinagar in which the latter called for defeat of "nationalist forces".
The Archbishop had last month written a letter urging members of the Christian community to save the country from "nationalist forces" as he said the "democratic fabric" of the country was at stake, amidst growing "sense of insecurity" among minorities.
The BJP MP also lashed out at the Congress, which, he alleged, symbolised "Rome rajya".
"The Gujarat polls are a contest between 'Ram rajya and Rome rajya'. Modi is the symbol of 'Ram rajya' in our times.
The BJP will certainly win," he said. The much-anticipated Gujarat polls are slated for December 9 and December 14.