"With any luck" vs "With a bit of luck"

[Sitifan]

1. With (any) luck, we'll be home before dark.

2. With a bit of luck, we'll be home before dark.

What's the difference in meaning between the above two sentences?
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Thank you very much for your reply.

[Barb_D]

I would say that the first make it sound more certain that you'll be home before dark. It's likely that you'll encounter at least a tiny bit of luck. In the second, you still need a bit of luck to make it - it sounds a bit less certain. But only a tiny bit.