Cars been starting on 2nd try about half the time

My 2004 Altima has been starting right up many times cold on the first try, sometimes waiting for a few seconds listing for fuel pump then trying helps, not always, but does always start on second try when it does act up which is a few times per day. it may start 5 times first try then maybe once second try, then behave again until the next day or so. No pattern at all. This has been going on for a while, now today no start at all, sounds like its out of gas sort of... a smell of burnt electrical maybe with a fuel smell possible from under the car. Ran great last night and all day yesterday (out of town)started on first try all day, pulled it in from the rain on first try at 11:30 pm and was kind enough to get sick in the garage this morning. I'm being told to replace the fuel pump but is it possibly the fuel regulator or??? I still heard pump sound this morning...
any suggestions??