2000 Chrysler Grand Voyager starting my car

For some time now we have had trouble getting the van to start. Seemed at 1st to be only after it sat a few days turn the key and just a click after a couple of trys it would start then seemed ok as long as we were driving it everyday. Recently it sat for a couple weeks and we could not get it started, also at this time had no lights radio ect so we thought it was the battery. We replaced it. The 1st few times it started right up no problems. Untill the next morning it started fine I drove to the store came out and just click it did start after a few trys but now it takes several trys every time. Any ideas?