This article is from the archive of our partner National Journal

Republicans are debating whether their path to the presidency in 2016 runs through the blue-collar Rust Belt states, or the demographically changing new South and Sunbelt states. For Democrats looking to retake the Senate, however, the formula is more clear-cut: Win back white working-class voters, or be consigned to a longer-term minority.

Most of the Senate battlegrounds run through the Midwest—Wisconsin, Pennsylvania, Illinois, Ohio—along with New Hampshire, which carries demographic similarities with those older, whiter Great Lakes states. To defeat the vulnerable Republican incumbents, Democrats have a challenging task ahead: Making inroads with blue-collar voters, who have been stubbornly resistant to the party's agenda since Barack Obama's time as president.

It's no coincidence that Democrats are turning to candidates with biographies tailored to appeal to this constituency. Illinois Rep. Tammy Duckworth announced her candidacy Monday against Sen. Mark Kirk by touting her working-class upbringing and service in the military. Former Ohio Gov. Ted Strickland, who represented a blue-collar district in the House, is the expected Democratic nominee against Sen. Rob Portman. Former Wisconsin Sen. Russ Feingold, a populist who championed campaign-finance reform during his last Senate tenure, is eyeing a comeback against the businessman who defeated him in 2010. And former three-star Navy Admiral Joe Sestak, a former two-term congressman from the working-class Philadelphia suburbs, is an early front-runner to face a rematch against Sen. Pat Toomey.

(RELATED: Democrats' Attempts to Win Back Working-Class Whites Are Getting an Early Test)

Exit polls show that Rust Belt Democrats performed dismally among non-college-educated white voters in these states in 2010. Feingold won just 40 percent of their vote in 2010, five points behind Obama's vote share in the state two years later. In Ohio, Strickland tallied just 40 percent of the working-class white vote in his reelection bid—a 20-point decline from his first gubernatorial campaign. Kirk's narrow victory in solidly Democratic Illinois was attributable to a 33-point margin of victory among blue-collar white voters. Sen. Kelly Ayotte won a whopping 62 percent of their vote in 2010, 9 points higher than in Scott Brown's losing campaign in 2014, and 14 points higher than Mitt Romney. (Sestak was the one exception to the rule, losing his race primarily because of lower turnout among minority groups, not weaker-than-usual support from whites.)

Democratic officials are hoping that, running in a presidential year when turnout from the party's base voters is higher, the environment will be sufficient to flip these Democratic-leaning seats back in their column. Indeed, in three of the five races, the Democrats are running challengers who were swept away in the 2010 wave (Feingold, Sestak, and Strickland). Obama won all five states in both of his presidential campaigns.

But that optimism assumes that Democratic support among white working-class voters already has hit rock bottom. At the end of the year, Obama's national approval with them dipped to 27 percent—nine points lower than after the 2012 presidential election. Republicans are already looking at contesting many of these traditionally Democratic Great Lakes states in the presidential election, especially if a candidate like Scott Walker emerged as the nominee.

(RELATED: The Emerging Republican Advantage)

Meanwhile, there's no guarantee that Hillary Clinton will offer much of an improvement over Obama in wooing working-class voters back to the Democratic fold. Last year, the Clintons spent plenty of political capital appealing to their old supporters in last year's key Senate races in Kentucky and Arkansas. Not only did Democrats Alison Lundergan Grimes and Mark Pryor get crushed by their GOP opponents, they performed as poorly among blue-collar voters as President Obama. Perhaps white voters in the Midwest will act differently than their Southern counterparts, but the 2010 results will give them pause.

Part of the challenge for Democratic candidates in the last election was their resistance to split more aggressively from an unpopular president, even when it was in their self-interest. (Paging Lundergan Grimes.) In 2016, with the presidential campaign occurring at the same time as these pivotal Senate races, that tendency to be a team player will be even greater—especially since the Senate battlegrounds are in more favorable territory.

But sounding more like an independent operator is an invaluable political asset—one that will be crucial for Democrats to have any hope of winning back disaffected voters alienated with the party. In her kickoff announcement Tuesday, Duckworth took a surprising step in that direction by critiquing Hillary Clinton for her secrecy regarding past State Department e-mails. Duckworth said she would "hold [Clinton] accountable" and called on her to testify before the Benghazi committee. Assuming he runs again, Feingold would be well-served to underscore his maverick reputation. He lost in 2010 because too many voters saw him as part of an overreaching Washington culture; he's hoping voters will remember his time taking on entrenched financial interests. Out of office, Sestak has been telegraphing his independence, feeling freer to criticize the president and his party's leadership.

For his part, Strickland trumpeted an endorsement from former President Clinton this week in hopes of recapturing some past glory. But relying on the Clintons may not be enough in 2016. Disaffected voters are looking for change, and for candidates who aren't beholden to the same old message.

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

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