An alternative, albeit likely a hiller one, is to head west to Columbia, NJ and cross the Delaware via the ped/bike bridge into Portland, PA, which is the eastern terminus of signed PA Bike Route V:http://www.dot.state.pa.us/public/pdf/bikes/state_mapV.pdf
Follow Route V to Emlenton PA (map #5) and then take the paved Allegheny River/Samuel Justus Trail all the way to Oil City, PA. From there, work your way up to Erie, where you can get on the Northern Tier eastbound in Niagara Falls, ON if you wish.
A few years ago I did a trip across PA starting in Vienna, OH. Made my way to Franklin, PA and took the ART south to Emlenton and then Route V as far east as Catawissa (map #21), before heading south. The trail is very nice and, except for maybe .5 miles, paved. The state also did a pretty good job with Route V. I found plenty of well-spaced camping and other services along the way. In Portland, PA, there is a private campground a bit of a climb above town. If you are willing to climb some more to save some $$, there is a second campground higher up the hill that charges only $10 for tent sites. Further west along Route V there is camping at Hickory Run State Park and in the town of White Haven (good grocery store and pizza places there) to the west of Hickory Run. From either, I believe it's easy enough to make the Catawissa/Bloomsburg area, where there is yet more camping, in one day.
While it's not the definitive source, I asked for Google Maps bike directions from Florham Park to Columbia, NJ. One option is returned was a 58 mile route that picks up the Paulinskill Valley Trail from a few miles west of Newtown to almost Columbia. Have never ridden the trail, but hear it's nice, albeit unpaved. The paved alternative between Newtown and Columbia is NJ 94. It has traffic in places depending on the day and time, but there is a good shoulder. I have ridden the entire stretch from Blairstown to Columbia and would not hesitate to do so again.
Let me know if you decide on this option. I have details regarding where I camped and shopped for groceries for dinner, etc.