Complex sentence: The bill passed into law, but northerners felt they had found a standard around which they could rally, while those in the South believed they should have an equal stake through slavery in the territories their blood and money had helped secure.
Split into simpler sentences: The bill passed into law, but northerners felt they had found a standard around which they could rally. Those in the South defended the new law, arguing that they should have an equal stake through slavery in the territories their blood and money had helped secure.