Apparently, as the results of the campaign would indicate.
That's a non-sequitur.
The campaign was designed and executed by McClellan. Lincoln had no say in the day to day operations. Mac bears the ultimate responsibility for a failed campaign.
We've been over this before.
First Intervention - Lincoln Destroys McClellan's Plan and Substitutes a New One
The plan was not McClellan's. Lincoln attempted to prevent McClellan's plan on 8th March by summoning the division commanders to vote on it. To his chagrin they voted 8-4 in favour of McClellan's plan. Thus Lincoln promoted the four that voted against it to Corps Commanders and on 13th March asked them to vote again. Happily for Lincoln, they rejected McClellan's plan and it was shelved. However, they substituted a completely new plan that Lincoln hated even more than McClellan's, and that plan was the movement to Fort Monroe.
McClellan had rejected the Fort Monroe movement in January, because a study by James Shields showed it would take six weeks to get past Yorktown. However, Lincoln was boxed himself in by calling a referendum that went against him, and orders McClellan to execute the Corps Commanders' plan.
Hence, your notion that the campaign was "designed by McClellan" is false. It was designed by McDowell, Sumner, Heintzelman, Keyes and Barnard, and set in motion by Lincoln.
McClellan in fact did a bit better than six weeks, and broke through to beyond it. This is despite Lincoln not ordering the Navy to cooperate (as he said he would), and Lincoln removing 5 divisions from McClellan's army, including the engineers.
Second Intervention - Lincoln Paralyses McClellan's Army on the Chickahominy
In response Lincoln came down to investigate, accompanied by Stanton, Seward, Chase and Tucker (***'t sec'y of war). Lincoln diverted forces from the pursuit of Johnston to the rather useless occupation of Norfolk (the rebels had abandoned it when they lost Yorktown). Seward, Chase and Tucker remained and concluded McClellan had been right all along;
"Providence Forge, May 14, 1862
ABRAHAM LINCOLN,
President
We [Seward and Chase] think that you should order whole or major part of General McDowell's, with Shields, up the York River as soon as possible, and order Whyman's flotilla up the James River. General McClellan moves to White House tomorrow morning.
WM H. SEWARD "
Lincoln doesn't want to send these forces, and so grudgingly orders that 1st Corps will go overland, rather than by water. McClellan is preparing to cross the Chickahominy and make for the James, where he can attack Fort Darling and open the river all the way to Richmond. On 1400, 18th May 1862, Stanton issues a peremptory order that McClellan's base must remain on the Pamunkey. This halts forward movement - McClellan is now under orders to wait for McDowell.
Six days later, the 24th May, was the day McDowell said he'd start marching. On this day Lincoln issues two sets of orders; firstly he says McDowell is coming, and that McClellan should split his own force (into three pieces, McClellan already holds a debouche on the right bank of the Chickahominy), and attack JR Anderson's "Army of the North", which he does. Only a few hours later Lincoln suspends the order to McDowell, but does not rescind any order to McClellan. Indeed, on 6th June McClellan is told that a division will come by water. McCall's division offloads at White House Landing 11th-13th June, and McClellan is told "It is intended to send the residue of McDowell's force also to join you as speedily as possible."
On the 12th McClellan transferred his CP to the right bank of the Chickahominy (to everyone's relief, Sumner was constantly panicking), and over the next few days McCall's division relieves Slocum's division along Beaver Dam Creek, and becomes the general reserve division.
McClellan moved to attack Richmond, within the parameters Lincoln set. Lee counterattacked, and McClellan defeated it. Then Jackson arrived behind his lines and cut him off from the supply base which Stanton specified on 18th May.
Third Intervention - Ordering McClellan to Retreat
McClellan on the James paralysed Lee. Richmond falling was still just a matter of time. Lincoln along with Halleck ordered McClellan's army withdrawn. This led to two full years with no serious threat to Richmond.