According to my numbers (which do vary in the number of total wins for each side), just a little more than half of the possible boards (50.05%) result in a 4-space win for white. 95% of white's winning combinations are in 4 moves vs. 78% of red's winning combinations. Also, there are substantially more 4-space wins for white than for red (32,801 vs 24,192).
At some point, I think one of those has to have some statistical significance, even if people being in control of what spaces are played in what order may counteract most of the disadvantage.