2006 Dodge Stratus starts only sometimes, why?

When I start my stratus in the morning it will start, idol for 1 - 1.5 sec then die.
It will do this a few times and then will not turn over unless the key is turned to
where the power is cut. The car will then turn over and start again but idol and
die. I've taken it to a auto shop before and they said it may be the anti-theft
system that my be screwed up.