In English I would say "excuse me". Some possibilities that come to mind are 请让，对不起，不好意思. I believe I have heard someone say "让!" before. Is that considered impolite?
The most polite way is to use:
excuse me -ABC
If you want to sound politer you can add a 一下 on the end: 借过一下.
让 is not super polite, with or without a 一下 but you could still get away using it.
A simple 不好意思 would also suffice but is not as polite as 借过.
In a polite way:
In an impolite way:
In most cases "劳驾" is the proper way: polite, effective and simple. If it doesn't attract the target's attention, you just need to repeat it louder.
"让" certainly is impolite. "请让" could be much politer, but still not as polite as "借过". The reason is that "过" indicates the intent of yourself (I want to pass), while "让" means request to others (You, make way).
"请让我过一下" is better than "请您让一下" for the same reason.
劳驾让一下。 or 借光让一下。 or 麻烦让一下。 or 请让一下。 You may replace 让一下 with 让一下道，