If U.S. Rep. C.W. Bill Young's retirement announcement upended Tampa Bay's political landscape, his death Friday makes it unrecognizable.

Young, 82, represented Congressional District 13 for nearly 43 years, routinely winning re-election by 20 percentage points as he became the longest-serving Republican in Congress.

He towered over the Tampa Bay delegation with influence and impact measured by hundreds of millions of dollars in earmarks he landed for Pinellas County and Florida.

Now his death turns Pinellas County into the ultimate bellwether of the national mood heading into the 2014 midterms.

A handful of congressional districts nationwide are as politically competitive as Young's. Seeing such a seat open up with no incumbent favored to win is rare, which is why so many local politicians and would-be politicians started gearing up as soon as Young announced his retirement less than two weeks ago.

But the dynamic is completely changed. Mounting a campaign over 12 months is vastly different from running in a multimillion-dollar special election just a few months away.

Prospective candidates and party officials on Saturday did not want to publicly discuss political machinations so soon after Young's death. But the new time frame is sure to prompt national party officials to heavily pressure candidates with the best-known names and money-raising potential to jump in — and the underdogs to clear out of the way in the name of delivering the seat to their respective parties.

That means former Democratic gubernatorial nominee Alex Sink and former Republican St. Petersburg Mayor Rick Baker look like the overwhelming favorites.

"Special elections in a compressed time frame favor known quantities: Neither side has much of an opportunity to build an organization or an image," said Republican consultant Rick Wilson of Tallahassee. "Candidates who step in it during a special have a hard time washing it off their shoes for Election Day."

Baker has voiced no interest in running ­— while also doing nothing to discourage speculation. He has long said he would not mount another major campaign until his children are out of high school (one is a senior, the other in 11th grade), but he's sure to face some arm-twisting in the coming days.

Sink has described herself as "very interested" and reaffirmed that interest Saturday, while the Democratic Congressional Campaign Committee has telegraphed its enthusiasm for her.

"A candidate — like Alex Sink — who has a strong record of solving problems would be extremely competitive in this district," the DCCC said as soon as Sink's name emerged.

Another significant, new consideration for any prospective candidates: Not only will they face a special election probably within a few months, but they also will face a re-election campaign a few months after that, including a potential, if not likely, primary challenge. A credible, conservative Republican alternative to Baker, for instance, may not be able to build a strong campaign in 120 days or so but in 10 months could be plausible.

Gov. Rick Scott has no authority to appoint a replacement for Young, but must schedule a special election to fill the seat. Florida law provides no specific time frame, but March 11 appears to be a likely date for either the primary or general election, given that more than a dozen Pinellas cities already have elections scheduled that day.

Get ready to see some Washington Beltway reporters on the campaign trail in Pinellas. The race should draw widespread attention as a barometer of the national political mood as the 2014 election cycle gets underway. Often the off-year gubernatorial races in New Jersey and Virginia serve as early signals of the public mood, but this year Republican New Jersey Gov. Chris Christie, and Democratic Virginia gubernatorial nominee Terry McAuliffe are heavily favored to win their races and the national repercussions are limited at best.

In Congressional District 13, however, we have the ultimate swing district, easily winnable by either party, though Republicans have the registration advantage.

Whether swing voter backlash over tea party Republicans in Washington shutting down the government over health care reform is short-lived or not, it may be clear by the results in Pinellas.

Young routinely won by big margins, but most races at the top of the ticket have been squeakers in recent years.

Barack Obama beat Mitt Romney in 2012 in the district with 50 percent, Sink beat Rick Scott in 2010 with 51 percent, Obama beat John McCain in 2008 with 52 percent, and George W. Bush beat John Kerry in 2004 with 51 percent.

Democratic lawyer Jessica Ehrlich, who ran unsuccessfully in 2012, had been campaigning for the seat months before Young announced his retirement. Other potential Democratic candidates include Sink, who says she would move from Hillsborough, and Pinellas County Commissioners Charlie Justice and Janet Long.

One key question: How much would Pinellas voters balk at electing someone who has never lived in Pinellas? Much of southern St. Petersburg already is represented by a Tampa resident, Democratic U.S. Rep. Kathy Castor.

The wider prospective Republican field includes well-known heavyweights as well as obscure long shots. Among them: Baker, Clearwater Mayor George Cretekos, former Clearwater Mayor Frank Hibbard, former state Rep. Larry Crow, Pinellas County Commissioner Karen Seel, former County Commissioner Neil Brickfield, former Young general counsel and personal attorney David Jolly, campaign consultant Nick Zoller, former long shot U.S. Senate candidate Sonya March, publisher Michael Pinson and Young's son, Bill Young II, whose name alone could make him a factor.

Adam C. Smith can be reached at asmith@tampabay.com.