Has an NFL game ever ended 19-0?
It has. 19-0 has been a NFL final 35 times in 18,236 games. The first was Akron Pros beat Rochester Jeffersons on October 30, 1921; the latest was Buffalo Bills beat Miami Dolphins on December 22, 2013.
That makes 19-0 the 159th most common final score out of 1,090 that have ever occurred in NFL. One point away, 20-0 has happened 71 times and 19-1 has happened never. Nearly all of its occurrences fall between 1920 and 1949.