Examining the Democratic claim that the race is tightening.

Sen. Barbara Boxer

Fox News alerts regularly herald the latest tsunami warnings, and the one today was for Okinawa, Japan. (Thankfully, nothing came of it.) I’ve gotten so many of these false alarms that each new warning now seems like assurance that there’s nothing to worry about. Democrats would like that analogy to describe this election year: Fox-fomented media hype about a big wave that never comes.

For the last several weeks, various Democrats have been arguing that their efforts to motivate their voters have been paying off. A slow-to-stir president is finally making a case about the dangers of Republican control of Congress. Polls are improving both nationally and in specific races. Today, Democrats announced that they’d raised $16 million this last quarter, their best haul in years.

But what does it all mean? First, don’t put away the foul-weather gear. There will be a wave. Republicans will pick up seats in the House and Senate. What’s at issue is the size of the swell (or amplitude, if you’ve been thinking of the wave in mathematical terms). It has gotten smaller. Even Republicans admit this. This was expected. The question is whether Democrats are “coming home” in a way that will continue, reducing losses far more than expected.

At this stage of a campaign, the losing side always comes up with an exciting theory. (In 2008, the McCain campaign had one.) Its purpose is psychological as well as tactical. People don’t like to lose, and look for hope in the smallest signs, such as the number of bumper stickers in a parking lot. And politics is unpredictable enough—and this year has been plenty crazy—that they have grounds for their hope. Plus, pundits and political strategists are often wrong.

Even if Democrats know how bad things are, there’s a tactical reason to pretend a rally is on. It’s a conjuring trick. It might actually energize everyone to rally for the team. That’s why various partisan columnists, strategists, and hope-mongers have heralded President Obama’s return to the campaign mode every week for the last several months. Today, White House Communications Director Dan Pfeiffer highlighted the president’s recent speech at the University of Wisconsin. “We have seen, I think—that we are beginning to make up the enthusiasm gap,” Pfeiffer said on a conference call with reporters. “We are making progress every day.”

There is actual evidence to back up the hope. National polls have all been trending back towards Democrats. When voters were asked whether they would vote for a Democrat or a Republican, the GOP had a steady lead over the last two months in an average of the polls. Now the two parties are almost tied. The Gallup poll shows the same narrowing, as does the Wall Street Journal/NBC News poll. Democrats usually discount Rasmussen polls as biased for the GOP, but even Rasmussen shows a nine-point Democratic surge. “There is life left in this baby,” says Simon Rosenberg of the New Democratic Network, who has been arguing the case for a reappraisal of the election for weeks.

Democrats also see their ground game paying off. In Ohio, organizers point to a recent CBS News/New York Times poll. By two-to-one, more respondents said they had been contacted by a Democratic Party volunteer than by a Republican one. Because the Obama ground game has been in operation for three years, in many cases these contacts are from familiar voices—a key in turning a contact into an actual vote.

This ground game helps explain why Gov. Ted Strickland, a Democrat, is now tied with his opponent in recent polls, Republican John Kasich. (Polls had shown a double-digit margin.) The power of the base was also demonstrated in the party’s fundraising totals. As theHotline pointed out, $16 million is the DNC’s largest month since 2002.

What accounts for the movement? Strategists offer a lot of theories. Unenthusiastic Democrats are finally paying attention and deciding to vote. Ads marking a clear contrast between candidates are sinking in, and so is the president’s message about this election being about a “choice” between two parties instead of an up-or-down vote on the Democratic agenda. There is no single, compelling GOP leader, and what people know about those leaders that do exist, they don’t like. In a recent National Journal/ Pew Research Center poll, 60 percent said they disapproved of GOP leaders. (Fifty-three percent had the same view of Democrats.).The GOP message—we’re not Obama—has penetrated all whom it will. In sum: The Republicans peaked too early.

Now that Congress has gone home, it can’t help but improve the situation for Democrats. The public does not like Congress or its leaders. There’s no more chance for them to bicker on television about stalled legislation and who is to blame for it.

But now for a reality check: How much does all of this good news get the Democrats? About 10 seats, says one longtime Democratic strategist involved in the races. Which is to say, they may lose 10 fewer seats than they expected. The math still looks bad for Democrats. The economy is still terrible, and people are still extremely glum about the country’s future. That bad atmosphere, plus Democrats defending seats in historically Republican territory, plus Obama’s low approval rating, means more than 20 or so seats currently held by Democrats are all but certain to go to Republicans. This tracks with the lowest possible prediction of GOP gains among political scientists who have made a study of making this guess. (The highest guess in the group of political scientists was a 51 seat gain by Republicans.)

After those certain victories, Republicans need 19 seats to take control of the House. If Democrats win a few GOP-held seats, maybe that number increases to 25. There are 40 to 50 Democrat-held seats, from which Republicans could take that number. The GOP doesn’t have to run the table. It just has to win about half the available seats. Nate Silver puts that probability at 67 percent, based on historical trends.

There are two pieces of data that may temper Democratic hopes. The first is that independents have been breaking away from the president and Democrats. How much stock you put in this group depends on how many actual moderates and independents you think there are. If you’re a Democrat and you think a lot of so-called moderates and independents lean Democratic, then you think they’re yours to get. If not, you believe that they’re gone, that it’s too late to convince them, and that it’s going to be a bad year. Third Way, a centrist Democratic group says that turning out the Democratic base won’t be enough to avoid a bad wave (PDF).

But for Democrats, the biggest bucket of cold water comes from looking at voters most likely to vote. In that group, the GOP has a big advantage that can’t be dented by the Democratic Party’s superior turnout model. With the election less than a month away, Gallup has now refined its methodology: Instead of looking at “registered voters,” where Democrats and Republicans are roughly even, it looks at “likely voters.” Among that group, and under two different turnout scenarios, Democrats are down by 12 percentage points. Gallup’s final likely-voter model has been historically accurate. If it is this year again, then a huge splash of water is heading straight for the Democrats.

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