But unlike campaign ads, issue ads carefully avoid expressly advocating the election or defeat of a candidate. Instead of urging viewers to vote for or against a particular candidate, the issue ad is likely to suggest they call the candidate to express their views on an issue. Political parties like to raise soft money, because there is no limit on the amount donors can give and few restrictions on who can contribute. Corporations and labor unions, for example, are barred from contributing to federal campaigns but can give the parties as much soft money as they want. There's a catch, though.
Soft money is easier for the party committees to raise but harder to spend.
It's not supposed to be spent directly to benefit candidates for federal office, but can only be spent on generic party building activities. Since the Senate and House campaign committees exist for the sole purpose of electing federal candidates, figuring out how to spend this bonanza is a challenge. They can't legally give it to their own candidates. And they can't use it for independent expenditures, which by law are campaign expenditures that must be financed with hard dollars. McConnell is the leading congressional foe of campaign finance reform legislation.