sad but true

though a couple of factors that can hinder you are
your upload speed, if you are on a home connection and say a pool in a data centre with a fat pipe find a block at similar times the pools block can propagate across the network quicker and thus be accepted faster.
and as we have been finding with Bitcoin recently, if you are creating large blocks (with lots of transactions) the block takes longer to upload and verify for the other nodes, again slowing propagation across the network.
Note, orphans are rare and these situations only arise when 2 blocks at the same height are found very close together