In the first section of the pamphlet, Paine contends that government is a necessary evil, because there needs to be a distinction between the people running society, and society as a whole. Society have power to begin with, because they choose their own government, but once they have done so, then give government the power to set the rules and boundaries of society.
Whenever people choose to live together in a group that cannot be managed by small consensus and discussion, it is necessary to have a government in charge, because man has a natural capacity for evil, and this needs to be curbed, with laws, civil requirements and a societal power structure that maintains safety and civility for all.
This leads to elections, because it's impossible for everyone to meet independently and decide upon who their next government should be. Elections are necessary to make sure that everyone has a say in who governs them, even those who do not have friends or associates to discuss a consensus with. Paine uses England as an example of a nation ruled by tyranny. England has a monarchy, and an aristocracy, running the country. Neither were elected and both operate using the rules of heredity, meaning that society as a whole has absolutely no say at all in the choosing of those governing them.
Section Two of the pamphlet enlarges on Paine's contentions about monarchial rule. If all men are equal when God creates them, then there should be no difference between a king and his subjects. He believes that rather than advancing a nation, a monarch can actually diminish one, by waging war or by trading one area of land for another. He is not a believer in a constitutional monarchy either; that is, a parliament that makes laws and a monarch that signs them into being. John Locke believed that this constitutional type of monarchy was able to control the actions of a monarch and in some small way make them answerable to their people, but Paine does not think these limits actually work, because the monarch is still at the top of the tree, and so any efforts to control him will become null and void because he has the ability to override any decision made by his parliament.
Section Three crosses the pond to talk about the state of affairs in America. Paine looks at the hostile relationship between England and the American colonies, concluding that American independence is the only workable way forward. He believes that an American version of the Magna Carta - a charter that made peace between King John of England and his rebel barons in 1215 - would protect the rights of both sides, and should be brokered by a third party that held no bias. Each colony should vote in five representatives who would be joined by two members of the Continental Conference, and they would meet in much the same way that a parliament or government meets. This would make sure that their freedom was maintained and that they would be able to achieve some level of religious freedom as well. Paine was the first to suggest a Congress as the most effective form of American government.
A colony would be divided into five districts, with delegates that went to represent each district in congress. Congress would meet once a year and elect a president. Once a colony or district had been represented by a president they would not be allowed to have another president until every colony had been represented.
Section Four is the most optimistic of the pamphlet. Paine believes that America has the potential to emerge victorious in their revolt against British colonial rule, both because of her manpower, and because of her naval capacity.