Yup. That's one reason there are so many delays on Amtrak trains - they may be scheduled to use the rails, but the CSX trains have priority on most of the track Amtrak uses.
Dem Congressman Patrick Murphy was on this train.
Patrick J. Murphy Verified account
PatrickMurphyPA
Im on @Amtrak train that just crashed. Im ok. Helping others. Pray for those injured
That I was told while being on an Amtrack train when it had to stop for that very reason.
Here is more stuff from the Blaze:
A lot of tracks around Philly are also used by SEPTA (local commuter rail), so you have three different entities sharing the rails. They do a pretty complex dance every day to manage the traffic, and it doesn't take much to have a serious screw up. Fortunately, trains generally go relatively slowly in that area... which probably helped a lot.