The lit cigarette will not ignite the gasoline itself when you just throw a lit cigarette into a bucket or can of gasoline because it's not a good enough ignition source.
But the lit cigarette can cause an explosion or fire if there are a lot of gasoline vapors around so you should never be smoking a cigarette while pumping gas or pouring gasoline into something.
Gasoline can be lit on fire because people have used gasoline to commit arson and the way they usually do it is to pour gasoline inside the house or building and then once outside they light the trail of gasoline with a lit cloth or something else.
It usually takes more than a match to get the gasoline lit but sometimes it will if you hold the match to the gasoline long enough.
Or someone might use a small torch to light the gasoline on fire.
It's the vapors though really that light gasoline on fire and you should never pour gasoline on a lit fire because it can and will flash back and burn you or anyone else around you.