I, Democratic Party, do take you, Republican Party, to be my partner in the rebuilding of this country to its greatest potential.  I promise that I will do my best to listen to your side and share any ideas that I feel will make this country a better place to live and to make sure that the citizens of this country benefit from our plans and decisions.

This would be a great start to have the two major political parties form a harmonious union and learn to work together to do what's right by all citizens and not work for the sole purpose of promote either side's agenda.  As with any marriage between two people or things, the only way for all concerned to benefit is to work together.