What was the idea behind popular sovereignty in the mid 1800

Which piece of legislation signed by lyndon johnson brought an end to barriers preventing minorities from participating in elections?

By the end of the 1800s, there was a change in the nature of the immigrants coming to the united states. immigration from northern europe—england, ireland, germany, and scandinavia—declined, while immigration from italy, russia, and austria-hungary grew. in fact, between 1900 and 1910, more than three-fourths of all immigrants came from these three countries. unfortunately, these countries were far removed england, the home of our founders, and the immigrants who came from them had a hard time adjusting to life in their new country.

Jacksonian democracy promoted new methods of political campaigning. one such technique was mudslinging. what was its effect on the presidential candidates?