Nissan Sentra starting prob

I recently bought a 2006 Nissan Sentra with 31000 miles.

The car runs great and starts right up first thing in the morning. However, often times after I drive it a half hour to work in the morning and leave it parked for a couple of hours, it won’t start on the first try when I get back in. It will always start on the second try.

Is this a problem that is common to Nissans, or is it something that I should be concerned about?