In a 5-4 opinion today authored by Chief Justice Roberts, the Supreme Court held today that the Bipartisan Campaign Reform Act ("BCRA", or "McCain-Feingold") could not lawfully ban ostensibly grassroots lobbying advertisements, paid with corporate funds, during the 30 and 60 day pre-election periods from which BCRA tried to erase them.    

Here's the radio ad in question:

PASTOR: And who gives this woman to be married to this man?
BRIDE’S FATHER: Well, as father of the bride, I certainly could. But instead, I’d like to share a few tips on how to properly install drywall. Now you put the drywall up...
VOICE-OVER: Sometimes it’s just not fair to delay an important decision.  But in Washington it’s happening. A group of Senators is using the filibuster delay tactic to block federal judicial nominees from a simple "yes" or "no" vote. So qualified candidates don’t get a chance to serve  It’s politics at work, causing gridlock and backing up some of our courts to a state of emergency.  Contact Senators Feingold and Kohl and tell them to oppose the filibuster.  Visit: BeFair.org.  Paid for by Wisconsin Right to Life (befair.org), which is responsible for the content of this advertising and not authorized by any candidate or candidate’s committee.

Does knowing that Sen. Feingold was up for re-election in three months make you believe it's actually an ad about his reelection, and not that issue?  Probably.  But in this case, unlike Bong Hits 4 Jesus, Chief Justice Roberts holds that an intent-based test would violate the First Amendment:

The test to distinguish constitutionally protected political speech from speech that BCRA may proscribe should provide a safe harbor for those who wish to exercise First Amendment rights. The test should also "reflec[t] our ‘profound national commitment to the principle that debate on public issues should be uninhibited, robust, and wide-open.’" A test turning on the intent of the speaker does not remotely fit the bill.
Far from serving the values the First Amendment is meant to protect, an intent-based test would chill core political speech by opening the door to a trial on every ad within the terms of [the ban], on the theory that the speaker actually intended to affect an election, no matter how compelling the indications that the ad concerned a pending legislative or policy issue. No reasonable speaker would choose to run an ad covered by BCRA if its only defense to a criminal prosecution would be that its motives were pure. An intent-based standard "blankets with uncertainty whatever may be said," and "offers no security for free discussion." ...

A test focused on the speaker’s intent could lead to the bizarre result that identical ads aired at the same time could be protected speech for one speaker, while leading to criminal penalties for another.... Such a test " ‘puts the speaker ... wholly at the mercy of the varied understanding of his hearers.’ " It would also typically lead to a burdensome, expert-driven inquiry, with an indeterminate result. Litigation on such a standard may or may not accurately predict electoral effects, but it will unquestionably chill a substantial amount of political speech.

Unlike Bong Hits 4 Jesus, then, when it comes to election-related speech, ambiguity gets resolved on behalf of the speaker:

In light of these considerations, a court should find that an ad is the functional equivalent of express advocacy only if the ad is susceptible of no reasonable interpretation other than as an appeal to vote for or against a specific candidate. Under this test, WRTL’s three ads are plainly not the functional equivalent of express advocacy. First, their content is consistent with that of a genuine issue ad: The ads focus on a legislative issue, take a position on the issue, exhort the public to adopt that position, and urge the public to contact public officials with respect to the matter. Second, their content lacks indicia of express advocacy: The ads do not mention an election, candidacy, political party, or challenger; and they do not take a position on a candidate’s character, qualifications, or fitness for office....

These cases are about political speech. The importance of the cases to speech and debate on public policy issues is reflected in the number of diverse organizations that have joined in supporting WRTL before this Court: the American Civil Liberties Union, the National Rifle Association, the American Federation of Labor and Congress of Industrial Organizations, the Chamber of Commerce of the United States of America, Focus on the Family, the Coalition of Public Charities, the Cato Institute, and many others.

   Yet, as is often the case in this Court’s First Amendment opinions, we have gotten this far in the analysis without quoting the Amendment itself: "Congress shall make no law . . . abridging the freedom of speech." The Framers’ actual words put these cases in proper perspective. Our jurisprudence over the past 216 years has rejected an absolutist interpretation of those words, but when it comes to drawing difficult lines in the area of pure political speech—between what is protected and what the Government may ban—it is worth recalling the language we are applying. McConnell held that express advocacy of a candidate or his opponent by a corporation shortly before an election may be prohibited, along with the functional equivalent of such express advocacy. We have no occasion to revisit that determination today. But when it comes to defining what speech qualifies as the functional equivalent of express advocacy subject to such a ban—the issue we do have to decide—we give the benefit of the doubt to speech, not censorship. The First Amendment ’s command that "Congress shall make no law . . . abridging the freedom of speech" demands at least that.

Justices Scalia, Kennedy and Thomas are ready to overrule McConnell v FEC, the modern precedent in this realm, because they believe no test works.  Justice Alito is almost ready.

And speaking for the four dissenters is Justice Souter, who believes this is a bad day for those who care about the influence of money on politics:

The corporate appellee in these cases, Wisconsin Right to Life (WRTL), is a nonprofit corporation funded to a significant extent by contributions from other corporations.12 In 2004, WRTL accepted over $315,000 in corporate donations, App. 40, and of its six general fund contributions of $50,000 or more between 2002 and 2005, three, including the largest (for $140,000), came from corporate donors....
Throughout the 2004 senatorial campaign, WRTL made no secret of its views about who should win the election and explicitly tied its position to the filibuster issue. Its PAC issued at least two press releases saying that its "Top Election Priorities" were to "Re-elect George W. Bush" and "Send Feingold Packing!" In one of these, the Chair of WRTL’s PAC was quoted as saying, " ‘We do not want Russ Feingold to continue to have the ability to thwart President Bush’s judicial nominees.’ "  ...
It was under these circumstances that WRTL ran the three television and radio ads in question. The bills for them were not paid by WRTL’s PAC, but out of the general treasury with its substantial proportion of corporate contributions; in fact, corporations earmarked more than $50,000 specifically to pay for the ads.... instead of providing a phone number or e-mail address, [the ads] told the audience to go to BeFair.org, a website set up by WRTL. A visit to this website would erase any doubt a listener or viewer might have as to whether Senators Feingold and Kohl were part of the "group" condemned in the ads: it displayed a document that criticized the two Senators for voting to filibuster "16 out of 16 times" and accused them of "putting politics into the court system, creating gridlock, and costing taxpayers money."
WRTL’s planned airing of the ads had no apparent relation to any Senate filibuster vote but was keyed to the timing of the senatorial election. WRTL began broadcasting the ads on July 26, 2004, four days after the Senate recessed for the summer, and although the filibuster controversy raged on through 2005, WRTL did not resume running the ads after the election. ...Any alert voters who heard or saw WRTL’s ads would have understood that WRTL was telling them that the Senator’s position on the filibusters should be grounds to vote against him.

The dissenters argued that "reasonable people are able to discern between ads whose primary purpose is to support a candidate and those intended to provide information about a policy issue," and allowed these ads to be regulated.

As for me, guh.  They're both right.  The dissenters are right that common sense and context tell us that these were probably election-related ads, but ultimately, I side with the 5-4 conservative majority (please don't hate me), because I just don't see how one can create a clear, workable test to distinguish the legitimate advocacy ads from the "loophole" ones within the timeframe of an election cycle.

Too, I wonder if the Internet largely moots this within a few years.  I gave that perspective at an American Constitution Society panel on the case; you can read my remarks here.