Meanwhile, back at the ranch -- as foreign events hog the spotlight -- why haven't Republicans sealed the deal on the coming election?
When summer began, the conventional wisdom was that the GOP sorta kinda probably maybe would take control of the Senate in November. As summer ends -- and it hasn't been great for President Barack Obama, which means it also hasn't been anything for the Democratic Party to write home about -- that same equivocal assessment still holds.
The Real Clear Politics website, which aggregates polls, rates nine Senate races as toss-ups. If incumbents Kay Hagan of North Carolina, Mary Landrieu of Louisiana and Mark Pryor of Arkansas manage to scrape out wins, the website calculates, Democrats will retain a 51-49 edge and Harry Reid gets to keep his job as majority leader.
Let's say that one of those Democrats falters -- or even two. It seems entirely possible that Bruce Braley could defeat Republican Joni Ernst in an Iowa race that polls show as a dead heat. Democrat Michelle Nunn may be gaining ground on David Perdue in Georgia, although a recent poll showing Nunn in the lead is probably an outlier. And the man who wants Reid's job, Minority Leader Mitch McConnell of Kentucky, is in a surprisingly tough race against Democrat Alison Lundergan Grimes.
All in all, you still have to give the edge to the GOP. But it is a surprisingly narrow and tenuous advantage in a year when some analysts were predicting a wave election in favor of Republicans.
So far, just ripples. Why could that be?
This time, the GOP managed not to nominate candidates whose views are so extreme -- or so wacky -- that they might effectively concede what ought to be safe seats. The party establishment made ideological concessions to the tea party wing, but managed to insist on nominees who have a chance of being elected.
The candidates may be plausible, but they're running on the wrong issues. Rather, the wrong issue: the Affordable Care Act.
"Repeal Obamacare" remains a rallying cry for the GOP's activist base -- perhaps less for the law itself than the president for whom it is named. But for independent voters, undoing health care reform is not the sure-fire issue Republicans hoped it would be.
The program is in effect. Some people who previously could not obtain health insurance now have it. Most people are unaffected. Despite all the dire GOP predictions, the sky has not fallen.
Yet Republican candidates say otherwise, describing a dystopian breakdown of the nation's health care system that simply has not occurred. And they go all tongue-tied when asked how they could manage to repeal Obamacare in the face of a certain veto by Obama -- or, more tellingly, just what they would put in place if they somehow succeeded.
Much of the news dominating the headlines this summer has been taking place overseas -- Russia's slow-motion invasion of Ukraine, the rise of the Islamic State in Syria and Iraq, whatever it is that seems to be happening in Libya. Blasting Obama for failed leadership is a guaranteed applause line, but GOP candidates are not even trying to articulate what the president should be doing differently.
Nor has the party developed an economic message that goes beyond the familiar standbys: tax cuts, spending cuts, deregulation. The public is clearly not thrilled with the state of the economy, but growth is up and unemployment is down. The claim that Democratic policies inevitably lead to ruin rings hollow.
Still, Democrats have an uphill fight, even if it's not nearly as steep as the GOP hoped. To hold the Senate, segments of the Democratic coalition who often skip midterm elections -- African-Americans, Latinos, younger voters -- will have to turn out. And polls show that Republicans maintain an edge in enthusiasm.
Which brings me to the wild card: immigration.
Obama is considering executive action that could give legal status to thousands or even millions of undocumented immigrants. Would that inflame conservatives and drive Republican turnout through the roof? Would it excite the Democratic faithful, especially Latinos, giving them a reason to vote?
This thing is unpredictable. And that's a surprise.
Eugene Robinson is a syndicated columnist.