What if McClellan had launched an overland campaig in 1862 rather than the Peninsula Campaign of OTL? Let's say Lincoln just refuses McClellan's idea of the Peninsula Campaign, or perhaps the CSS Virginia is more successful and thus, transporting troops is too risky for the moment. How would McClellan have initiated such a campaign and how successful would he have been? Keep in mind that Joseph E. Johnston would have been the Confederate commander for the time being. Thanks.