Actually, the Confederates took my battlefield casualties than the Union, so they took more than quite a few. I did the sum total for "battlefield" casualties for the entire war and the Confederates took at least a 4% higher battle field casualties. The aggregate battle death toll percentage favored the Union. Between 1.5 million and 2.4 million Union soldiers served during the Civil War, whereas 750,000 to 1 million Confederate soldiers served. Consequently, the Union had an a estimated 40-50% more men than the Confederates, and took only an estimated 16,000 more casualties. Battle death percentages are a good metric: the Union battle casualties were 110,000 and the Confederacy was 94,000, that equates to the Union had roughly 16-17% battle mortality rate and the Confederacy had a 20% battlefield death mortality rate. The problem is that when people read about casualties they don't notice that they are reading the sum total of deaths: battle deaths, disease and prisoners of war and that's why they misconstrue the mortality rate of 15% for the Union and 12% for the Confederacy, but strictly from a battlefield mortality the Confederacy had a 20% mortality rate and the Union around 16-17%. People act like the Union took a 50% battlefield casualty rate and the Confederates took 20%, and what was all lost because the Union had superior numbers. Nonsense. The bottom line: the Confederates had a higher battlefield death rate, by like 4% and that was a huge percentage. Did not the Confederate census pontificate that they had a 10:1 KIA ration advantage prior to the war? Well, at the closing of the war the Union had a 3:1 KIA victory(use search engine for sources). I'm talking about "battlefield" casualties, not total war deaths. I think it is safe to say the Confederates were innumerate and were too proud for their own good. Las Vegas would have made billions of dollars on that one.
I personally believe the biggest mistake of the war was not a strategy or tactical blunder but a "preparation" for the war. They lacked the industrial capacity for a complete war effort. If so, they could have won because they were dug in(fortified) on their own turf in a era where fortifications held the advantage.