I wish I could say that I heard a call to pray before the election in 2000. We prayed, but sporatically. It was only after the Florida hang-up that the Lord seemed to say that He was holding the election in the balance primarily to see if His people cared enough to pray. That's when we determined to get serious. But it wasn't our determination which got us through that month of daily prayer. It was like we were carried along by His will. We dared NOT pray. It became as important as breathing. And God has been gracious to keep us praying over the past four years; and we don't have any sense that He's released us from that ministry. Which gives us all great confidence that God intends to do some mighty works in and through our nation. But it won't be released except through prayer.
It's okay that you weren't called to pray until the mess in Florida - what's important is that you answered WHEN you were called. Obedience is the high calling of God!
God has also been gracious in allowing me to pray over the past almost 5 years. There have been times when I've not been impressed to pray and I've asked Him why. He's assured me that those are simply times of rest in the midst of the battle. Once you've been drawn into that kind of intimacy with the Creator of Heaven and Earth, you don't want to live a moment without it.
It sounds as though 1 Samuel 12:23 is true for both of us, "As for me, for be it for me that I should sin against the Lord by failing to pray for you."
I believe that God does intend to do some mighty works in and through our nation and He has allowed some of us to be on the "inside track" with Him. I find that I look at everything that is happening in the world in light of His mighty plan. The battle ahead of us is fierce - fortunately, the war is already won.
For from Him and through him and to Him are all things. To Him be the glory forever! Amen Romans 11:36