This article is from the archive of our partner National Journal

One of the most underappreciated stories in recent years is the deterioration of the Democratic bench under President Obama's tenure in office. The party has become much more ideologically homogenous, losing most of its moderate wing as a result of the last two disastrous midterm elections. By one new catch-all measure, a party-strength index introduced by RealClearPolitics analysts Sean Trende and David Byler, Democrats are in their worst position since 1928. That dynamic has manifested itself in the Democratic presidential contest, where the bench is so barren that a flawed Hillary Clinton is barreling to an uncontested nomination.

But less attention has been paid to how the shrinking number of Democratic officeholders in the House and in statewide offices is affecting the party's Senate races. It's awfully unusual to see how dependent Democrats are in relying on former losing candidates as their standard-bearers in 2016. Wisconsin's Russ Feingold, Pennsylvania's Joe Sestak, Indiana's Baron Hill, and Ohio's Ted Strickland all ran underwhelming campaigns in losing office in 2010—and are looking to return to politics six years later. Party officials are courting former Sen. Kay Hagan of North Carolina to make a comeback bid, despite mediocre favorability ratings and the fact that she lost a race just months ago that most had expected her to win. All told, more than half of the Democrats' Senate challengers in 2016 are comeback candidates.

On one hand, most of these candidates are the best choices Democrats have. Feingold and Strickland are running ahead of GOP Sens. Ron Johnson and Rob Portman in recent polls. Hill and Hagan boast proven crossover appeal in GOP-leaning states that would be challenging pickups. Their presence in the race gives the party a fighting chance to retake the Senate.

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But look more closely, and the reliance on former failures is a direct result of the party having no one else to turn to. If the brand-name challengers didn't run, the roster of up-and-coming prospects in the respective states is short. They're also facing an ominous historical reality that only two defeated senators have successfully returned to the upper chamber in the last six decades. As political analyst Stu Rothenberg put it, they're asking "voters to rehire them for a job from which they were fired." Senate Democrats are relying on these repeat candidates for the exact same reason that Democrats are comfortable with anointing Hillary Clinton for their presidential nomination: There aren't any better alternatives.

For a portrait of the Democrats' slim pickings, just look at the political breakdown in three of the most consequential battleground states. Republicans hold 12 of Ohio's 16 House seats, and all six of their statewide offices. In Wisconsin, Republicans hold a majority of the state's eight House seats and four of five statewide partisan offices. In Pennsylvania, 13 of the 18 representatives are Republicans, though Democrats hold all the statewide offices. (One major caveat: Kathleen Kane, the Democrats' once-hyped attorney general in the state, is under criminal investigation and has become a political punchline.) These are all Democratic-friendly states that Obama carried twice.

If Strickland didn't run, the party's hopes against Portman would lie in the hands of 30-year-old Cincinnati Councilman P.G. Sittenfeld, who would make unexpected history as one of the nation's youngest senators with a victory. (Sittenfeld is still mounting a long-shot primary campaign against Strickland.) Without Feingold in Wisconsin, the party's only logical option would be Rep. Ron Kind, who has regularly passed up opportunities for a promotion. Former Milwaukee Mayor Tom Barrett already lost to Gov. Scott Walker twice, and businesswoman Mary Burke disappointed as a first-time gubernatorial candidate last year. And despite the Democratic establishment's publicized carping over Joe Sestak in Pennsylvania, the list of alternatives is equally underwhelming: His only current intra-party opposition is from the mayor of Allentown.

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In the more conservative states, the drop-off between favored recruits and alternatives is even more stark. Hagan would be a flawed nominee in North Carolina, but there's no one else waiting in the wings. The strongest Democratic politician, Attorney General Roy Cooper, is running for governor instead. And in Indiana, the bench is so thin that even the GOP's embattled governor, Mike Pence, isn't facing formidable opposition. Hill, who lost congressional reelection campaigns in both 2004 and 2010, is not expected to face serious primary competition in the race to succeed retiring GOP Sen. Dan Coats.

Even in the two swing states where the party landed young, up-and-coming recruits to run, their options were awfully limited. In Florida, 32-year-old Rep. Patrick Murphy is one of only five House Democrats to represent a district that Mitt Romney carried in 2012—and his centrism has made him one of the most compelling candidates for higher office. The Democratic Senatorial Campaign Committee quickly rallied behind his campaign (in part to squelch potential opposition from firebrand congressman Alan Grayson). But if Murphy didn't run, the alternatives would have been limited: freshman Rep. Gwen Graham and polarizing Democratic National Committee Chair Debbie Wasserman Schultz being the most logical alternatives.

In Nevada, Democrats boast one of their strongest challengers in former state Attorney General Catherine Cortez Masto, vying to become the first Latina ever elected to the Senate. But her ascension is due, in part, to the fact that other talented officeholders lost in the 2014 statewide wipeout. Democratic lieutenant-governor nominee Lucy Flores, hyped by MSNBC as a "potential superstar," lost by 26 points to her GOP opponent. Former Secretary of State Ross Miller, another fast-rising pol, badly lost his bid for attorney general against a nondescript Republican. By simply taking a break from politics, Cortez Masto avoided the wave and kept her prospects alive for 2016.

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This isn't an assessment of Democratic chances for a Senate majority in 2017; it's a glaring warning for the party's longer-term health. If Clinton can't extend the Democrats' presidential winning streak—a fundamental challenge, regardless of the political environment—the party's barren bench will cause even more alarm for the next presidential campaign. And if the Democrats' core constituencies don't show up for midterm elections—an outlook that's rapidly becoming conventional wisdom—Democrats have serious challenges in 2018 as well. It's why The New Yorker's liberal writer John Cassidy warned that a Clinton loss next year could "assign [Republicans] a position of dominance."

By focusing on how the electorate's rapid change would hand Democrats a clear advantage in presidential races, Obama's advisers overlooked how the base-stroking moves would play in the states. Their optimistic view of the future has been adopted by Clinton, who has been running to the left even without serious primary competition.

But without a future generation of leaders able to compellingly carry the liberal message, there's little guarantee that changing demographics will secure the party's destiny. The irony of the 2016 Senate races is that Democrats are betting on the past, running veteran politicians to win them back the majority—with Clinton at the top of the ticket. If that formula doesn't work, the rebuilding process will be long and arduous.

This article is from the archive of our partner National Journal.

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