I think deadlines are a sufficient condition for procrastination but not a necessary one. And even starting a project earlier is no guarantee of avoiding a last minute crunch. (When I was studying I'd start projects on time, get the "hard parts" done, but still end up finishing them off at the last minute. Whether that's a function of anchoring or just plain vanilla Planning Fallacy, I'm not sure).
Without a deadline, can you still procrastinate? Of course, but the consequences of not starting are less immediate, but still potentially severe. If you don't finish writing an essay by the deadline, you fail a course. If you don't submit an application, nothing happens now, but restrict your options later. If you never exercise, you're more likely to get sick as you age.
So having decided to start, how do you maintain momentum? From a comment above, breaking down a single project into sub tasks with their own deadlines is a great start. But there's still a trap here - the comforting thought that some sub tasks will take less time than others, and you've got heaps of time to the actual deadline to catch up. Quantifying what you'll achieve (e.g. I will write the introduction and conclusion by the end of the week) provides a concrete goal and also harder to lie to yourself about how much time you have.
The phenomenon of anchoring seems to predict that deadlines will cause you to start a project near the deadline.
In more detail:
Any number you consider as an answer to a question will become an anchor and draw your answer towards it. Since you consider a deadline as a time to finish a project, your decision about when you should actually finish the project will be drawn towards it.
That'll make you start the project later, even though you know consciously that planning to finish a project near the deadline is a bad idea.
It's analogous to an example from Kahneman's Thinking, Fast and Slow—people buy more cans when there's a sign telling them that they can only buy 10.
So, what I'm predicting is that anything that prevents anchoring will reduce procrastination when there's a deadline. Consciously deciding when you plan to finish by adjusting from a much earlier time, maybe?
EDIT: Brendon_Wong points out that "procrastination" really refers to putting things off, which has an emotional cause. I think he's right. What I'm talking about isn't really a procrastination, then, but bad planning.