this site has some good info on it, and about a quarter of the way down the page it breaks down the figures like this:

Ukrainians 5.5 - 7 million Jews (of all countries) 6 million +
Russian POWs 3.3 million +
Russian Civilians 2 million +
Poles 3 million +
Yugoslavians 1.5 million +
Gypsies 200,000 - 500,000
Mentally/Physically Disabled 70,000- 250,000 Homosexuals Tens of thousands
Spanish Republicans Tens of thousands
Jehovah's Witnesses 2,500 - 5,000
Boy and Girl Scouts, Clergy, Communists, Czechs, Deportees, Greeks, Political Prisoners, Other POWs, Resistance Fighters, Serbs, Socialists, Trade Unionists, Others Unknown Table assembled from figures quoted by Milton; Lukas 38-39, 232; Gilbert 824; Berenbaum 123; and Holocaust Internet information sites.

The six million figure used in the Jewish death toll is an estimate for total lives lost. These Jewish lives were taken by a number of groups, not just Nazis. The six million figure includes Jewish lives lost in other countries as well, not just Germany, and by the various modes of killing, not just camp deaths. Ukrainian deaths were due to Russian and Nazi perpetrators alike, some killed on "acquired" German soil, others killed on Russian soil, some killed outright, others slowly worked or starved to death.