Millions of words have been written about the age gap in voters this year. But a new poll today from Gallup says it’s actually the voters in the middle – in their 40’s – who could determine the election’s outcome.

John McCain and Barack Obama are tied (46-46 percent) among 40-something voters. Not surprisingly, Obama leads McCain among voters younger than 40 and McCain leads Obama among voters 60 and older. Obama has a slight edge among voters in their 50’s.

The Gallup pollsters write: “Forty-something voters are a politically interesting group because some of the common political divides in the U.S. electorate are not evident within this particular age group.” For example, there is no gender nor educational gap in Obama and McCain supporters in their 40’s.

The survey was done June 5-11 and has a margin of error of +/- 3 percent.