If efforts at compromise failed, however, and a sweeping abortion ban somehow made it to the Senate floor, the Democrats might mount a filibuster (assuming it was still available for ordinary legislation). But whether or not the federal abortion ban progresses very far, the mere threat of its passage might be enough to push the Democrats over the edge in the 2008 elections, helping them to recapture at least the Senate and perhaps even the House. Pro-life voters are currently better mobilized than their pro-choice opponents; surveys have shown that pro-life voters rank a candidate’s position on abortion among their top three concerns, as opposed to pro-choice voters, who rank it substantially lower. But the day after Roe, those priorities would undoubtedly change. Suburban Republican women, a number of whom are fiscally conservative and socially liberal, might switch parties in many states, giving Democrats the margin of victory they need to win the Senate in a country virtually at parity. Virginia, for example, currently has two Republican senators, John Warner and George Allen, but it’s not clear how either would do in a race where swing voters were energized by the issue of choice. (Even the ardently pro-life Allen told Newsweek that he would have vetoed a South Dakota–style law if he were still governor of Virginia, and declared on Meet the Press that the federal government shouldn’t be in the business of passing abortion laws, but should instead leave the issue to the states.) Throughout the South, moderate Democrats in the mode of John Edwards might beat conservative pro-life Republicans in enough states to shift the Senate.

Even in the House, where there are fewer competitive seats due to gerrymandering, the rise of abortion moderates could give the Democrats a fighting chance to gain the seventeen seats necessary to win a majority. “Gerrymandering depends on existing voting patterns holding, and this would change existing voting patterns,” says Bill Stuntz of Harvard Law School. “You have a lot of sixty-forty districts, but if national public opinion on abortion shifted, at some point Democrats would win a lot of seats that Republicans have been winning by more than ten points, just as Republicans did when they took the House in 1994.”

It’s entirely possible, therefore, that if Roe were overturned, both the House and the Senate would be Democratic after the 2008 elections. What would happen next? The moment the new Congress was sworn in after a national election dominated by abortion, Democrats in both chambers would introduce a federal bill to codify the protections of Roe v. Wade. It might look very much like the Freedom of Choice Act, which has languished in Congress for the past decade. That act would protect a woman’s right to choose before fetal viability and allow states to ban abortion after fetal viability, unless the life or health of the mother is threatened. The Freedom of Choice Act was introduced in the Democratic Congress that followed Bill Clinton’s election in 1992 and was defeated in part because pro-choice extremists insisted that it didn’t go far enough in protecting late-term abortions. The more moderate Democrats elected after the overturning of Roe, one hopes, would not make the same mistake. If a Democratic Congress proposed the Freedom of Choice Act, moderate pro-choice Republicans in swing states, like Specter in Pennsylvania, would face tremendous pressure to support it. But even with some Republican support, it’s not certain that a Democratic Congress could muster the sixty votes necessary in the Senate to defeat a Republican filibuster (assuming, once again, that it still exists). NARAL Pro-Choice America estimates that in the current Congress, there are about fifty potentially pro-choice senators, thirty-three of them reliable and seventeen swing votes. Unless the election of 2008 were a Democratic sweep, a Republican minority might still be able to block a federal law protecting early-term abortion, even if a majority of the Senate and the country supported it. Or a Republican president could threaten to veto the Freedom of Choice Act. But if Roe is overturned, there may not be a Republican president.

III. The White House

If Roe falls in June 2007, abortion will almost certainly become the central issue in the 2008 presidential election. And Republicans are already worrying about the political fallout. “We’d be blown away in the suburbs, and you wouldn’t see another Republican president for twenty years,” a pro-choice Republican congressman recently told Roll Call. Karl Rove has long dodged questions about whether he thinks Roe should be overturned, and Ken Mehlman, the head of the Republican National Committee, has refused to comment on the South Dakota law, making it clear that he’d rather talk about anything else. The fact that Electoral College battleground states, such as Ohio and Pennsylvania, are likely to be facing the fiercest state fights over abortion can’t be good news for the GOP.