Was stephen douglas for slavery or against it?

Answer 1

He was ambivalent. He thought the issue should be decided locally, but he was staunchly for the Union. After his defeat by Lincoln he undertook a mission for the President to rally support for the Union in the South. Many attirbute his untimely death by typhoid in 1861 to these efforts.

Answer 2

Basically pro, with qualifications. He wanted slavery to be decided by local populations, so that it would not be a national issue--however, because he wrote the Kansas-Nebraska Act; he was associated with the Fugitive Slave Act.