Democrats got incensed when Robert Gibbs conceded the possibility that Republicans could retake the House in the upcoming midterm elections, which the White House meant as a warning — as well as an acknowledgment of reality.  Imagine what their reaction will be when they read William Galston’s analysis of the Senate races in The New Republic.  While most analysts predict healthy gains for Republicans but control to remain firmly in Democratic hands, Galston says the Senate is now in play:

To retain control, Democrats need at least 50 seats. They start with 45 seats that are safe or not up for election this year, and there are three more races (NY, CT, and OR) that they are likely to win, for a total of 48. (The comparable number for Republicans is 41.) That leaves 11 seats in play. …

There are some elections years (1980, 1986, and 2006 come to mind) when most of the close races tip in the same direction, producing a shift of control. 2010 could be another.

It’s entirely possible that when the dust settles this November, Republicans will have hit the trifecta—President Obama’s former seat, Vice President Biden’s former seat, plus the Senate majority leader’s seat.

Galston lists eleven seats that Democrats may well lose in November and the most recent polling he had before publication.  Some of those polls have shifted a bit; the latest Rasmussen survey on the Boxer-Fiorina race puts Boxer back into the lead, and another on the Nevada race that brings Reid within three of Angle.  Still, the implication is clear — a national momentum shift could allow Republicans to sweep these races and put both chambers of Congress back in Republican hands.

That still appears to be a long shot, even with this list.  On the other hand, each of these races look winnable now for Republicans, even in such usually Democratic states as Washington and California, where weak incumbents will face a huge anti-incumbent reaction this year.  Galston holds out hope that Rand Paul will fall to Jack Conway in Kentucky, but that seems less likely than Russ Feingold winning his re-election fight in Wisconsin against Ron Johnson.

If the GOP can gain five or six seats, it will still be a big victory and will force Democrats to start compromising.  They won’t get legislation through the upper chamber simply by flipping one Republican vote any longer, which will make the White House and Senate Majority Leader — whoever it turns out to be in the 112th — come to Republicans to craft middle-of-the-road bills on shared priorities, or get nothing done at all.  But if Galston’s prediction comes true, it would be an utter disaster for Barack Obama, and shine an even brighter spotlight on his leadership inadequacies.

Update: Here’s an interesting update on the Wisconsin race.  The Johnson campaign announced it has raised over $550,000 in the second quarter.  If that seems a little low, remember that Johnson only started his campaign on May 17th — which means he raised that money in about seven weeks.