Doesn’t trying to prevent a candidate from being on the ballot constitute an assault on democracy?

There is a group of progressives in North Carolina trying to prevent Rep. Madison Cawthorn from running for re-election. This group of activists believes that Madison Cawthorn should be disqualified simply because he watched Trump’s speech at the Capitol on January 6th, 2021. Madison Cawthorn said that this group was very close to succeeding in their efforts. This is Un-American!