Thanks to the retirement of Rep. C.W. Bill Young (R-Fla.), a Tampa-area House seat is suddenly in play for Democrats, who need every break they can get to have even an outside chance to compete for the House majority in 2014.

Young's retirement brings the number of open House seats to 15, and his district is the only toss-up among them, according to the Cook Political Report.

22-term Florida Rep. Bill Young announced his retirement on Wednesday. His seat is unlike almost any other in the country. (The Washington Post)

As a general rule, long-serving lawmakers represent highly partisan congressional districts. Of the 20 most senior members of the House, only Young and one other congressman serve swing districts. And Young is the only Republican among them who represents a district that voted for President Obama last year.

Yet Young won his district by 16 points last year. It was his second-smallest margin of victory in over 40 years. His seat is safe, but only if he’s sitting in it. Tampa Bay Times political editor Adam C. Smith calls it “the most competitive seat...anywhere in Florida, if not the southeast.”

It’s hard to argue with that. President Obama beat Mitt Romney in the 13th last November by a 50 to 49 point margin. Obama did slightly better in 2008, winning by four points. George W. Bush beat John Kerry there 51 to 49, and lost to Al Gore by the same margin.

District-level voter registration data is not available, but Pinellas County, which makes up most of the 13th, has almost exactly the same number of registered Democrats as it does Republicans.

As Smith points out, one question to ask is whether former Gov. Charlie Crist, the Republican Independent Democratic mainstay of Florida politics, will enter the race. His parents live in the district, and he lives just outside of it. Crist is thought to be considering another run at the governorship. Incumbent Gov. Rick Scott (R) had a 40 percent approval rating in June.

Without Crist, the early front-runner on the Democratic side has to be Jessica Ehrlich, a St. Petersburg attorney who lost to Young last November and in April announced she would challenge him again in 2014. Ehrlich was out-raised by a 2 to 1 margin last year, but still pulled in over $500,000, thanks in some measure to the endorsement of the national Democratic group Emily’s List.

Among the Republicans who might be interested in the seat: a sitting state senator, a county commissioner, two former mayors, and Young’s son Billy.