Some questions and answers about the campaign finance law now that a three-judge federal court panel has struck down key parts:

Q: What does the ruling say?

A: Political parties can return to raising soft money — corporate and union contributions of any size and unlimited donations from any source. The parties can spend this money on party-building costs such as get-out-the-vote drives and overhead, but not for issue ads or helping specific candidates.

The judges rejected a broad ban on election-time political ads by interest groups. That barred a range of groups — sometimes financed with corporate and union money — from airing issue ads mentioning federal candidates in those candidates' districts in the month before a primary election and within two months of a general election.

But the court upheld backup rules blocking many groups from airing ads that promote, support, attack or oppose a candidate at any time. It remains to be seen how far interest groups can go when featuring candidates in ads.

Also turned aside was a requirement that political parties choose between coordinating spending with candidates — making the spending subject to federal contribution limits — and spending independently to help them, without limits.

The court upheld a tougher standard for determining how much interest groups, political parties and candidates can coordinate election activity before interest group or party spending is considered a donation to a candidate subject to federal limits.

Q: Did challengers to the law get everything they wanted?

A: No. They are likely to ask the Supreme Court to strike down the soft money ban, political ad restrictions and coordination rules entirely. Those suing cover the political spectrum, including the National Rifle Association, Republican National Committee, AFL-CIO, U.S. Chamber of Commerce and California Democratic and Republican parties.

Those defending the law — including the government and the law's sponsors — are expected to ask the court to keep the whole law intact.

Q: If the Supreme Court gets the last word, does it really matter what the lower court did?

A: The lower court made it matter — at least for a few days — by putting its ruling into effect immediately. Sponsors of the law say they will ask for an order to block the ruling from taking effect. Those challenging the law could do the same for parts of the ruling they oppose.

Q: What if the court ruling is not blocked right away? Will politicians start raising soft money again?

A: Party officials say it is too soon to decide whether they will raise soft money for next year's elections. If they do raise it, it is unclear what they could with it leading up to the presidential election. The Supreme Court is not expected to hear the case until this fall at the earliest, and it could uphold the soft money ban, changing the rules again.

The Federal Election Commission may be asked by donors, candidates, parties and interest groups to spell out exactly what to do in the meantime.

Q. If the Supreme Court upholds the soft money ban, what kind of money could people give?

A. Limited donations known as hard money. Like the old rules, the new law lets individuals and political action committees — funded by individuals — give limited contributions. In fact, it lets individuals give twice as much as before: $2,000 per candidate per election.