Final answer:
The emergence of Super PACs has weakened the congressional ban on soft money.
Step-by-step explanation:
The emergence of Super PACs has weakened the congressional ban on soft money. Super PACs are independent expenditure-only committees that can raise unlimited sums of money from corporations, unions, associations, and individuals, and then spend that money to campaign for or against candidates or ballot initiatives. This was made possible by the Supreme Court ruling in Citizens United v. Federal Election Commission, which stated that limiting independent political spending from corporations and other groups violates the First Amendment right to free speech.