I think it is a bit complicated.
If you pay by creditcard you may be able to claim back from them if the company goes bust. But I am sure that only applies if you book with a British company, so for example if you book direct with a hotel abroad or a foreign booking agency you wouldn't be covered.
You wouldn't be covered by the Package tour regulations, so for example if you were abroad whilst a failure took place you may have to make your own way home paying upfront and then claiming back on your travel insurance.
If you book your accommodation via an agency who goes bust like Freedom direct did and ScotTravel ahve this week, it seems you have to pay again for your accommodation.
Then when you get back try and get a refund from your card, as often the agencys have not paid the money on to the hotel even though you have paid them, so the hotel will no honour the booking unless you pay again.
There are a few threads on here about what ATOL do, it might be worth either reading them or hopefully someone who fully understands ATOL will reply. These are the people who I beleive cover your flight. Dont think ABTA would apply as they are the Association of British Travel agents and you would not be using a travel agent.