No, Travelocity is under no obligation. They'll probably try to help as much as they can with finding alternative flights, assuming any are to be found. They won't pay for the alternative flights for you.
If you paid with a credit card within 60 days prior to the airline going out of business, then your credit card is mandated to refund your money. Otherwise, your money is subject to total loss.
Sorry, I wish the news was better, but look at the bright side: Twice in the last couple of years, the federal judiciary has chosen to take the debt burden of a major airline like Delta onto the American taxpayers, rather than let it go out of business. They'll probably do that again.