The magic number for Democrats

• AFL-CIO political director Mike Podhorzer is worried about Democrats' standing with working class voters


• Podhorzer: "Democratic victories are powered by the votes of the people who are more financially stressed"

Washington (CNN) -- The number making Mike Podhorzer anxious these days is 15.

That's the lead Democrats have over Republicans among working class voters in the final days of the 2014 midterm elections, according to his polling at the AFL-CIO, the nation's largest labor federation. That might seem good for Democrats, but in modern times, the party always wins voters making $50,000 or less.

For Podhorzer, the AFL-CIO's political director and one of the Democratic party's top thinkers on voter turnout, it's the spread that matters.

"Democratic victories are powered by the votes of the people who are more financially stressed," Podhorzer said in an interview with CNN at the labor federation's Washington offices, just up the street from the White House. "That's been the case going back to the New Deal. When working class people turn out and vote Democratic, that more than compensates for the advantage that Republicans have among upper income voters."

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In other words, with GOP dependably winning upper-income Americans, it's up to Democrats to run up the numbers with downscale voters, who made up about 40% of the electorate in the last election.

When Democrats clobber Republicans nationally among working class voters — as they did by 22 points in 2012 — they win. When the margin is tighter — it was only an 11-point win for Democrats in 2010 — they lose.

The 55-40 lead Democrats are clinging to among people making under $50,000 is wider than the 50-39 lead they had earlier this summer, making this year's outcome harder to predict. Podhorzer said it does explain why Democrats are still in the hunt heading into next Tuesday, suggesting that next week's election won't resemble the GOP tidal wave of 2010.

But it still makes him nervous.

Too many Democratic campaigns have failed to rally their working class base, Podhorzer said, choosing instead to run on wedge issues -- like Sen. Mark Udall's relentless opposition to a personhood amendment in Colorad -- rather than broader economic populism.

"It's very dangerous," he said. "I think that picking niche issues and trying to run on a collection of issues and contrasts in this environment is less effective than mobilizing the voters they need to turn out."

"Throughout this cycle, polls have shown Republican voters to be more enthusiastic, because Democrats have been taking an approach in general that's more about slicing into independent voters and into the middle, and has left the base fairly unmotivated," he said.

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The Democrats who have nurtured working class voters with an economic message — like Gary Peters in Michigan and Al Franken in Minnesota — aren't getting much national attention, he said, because they have pulled away from their opponents and aren't being covered by the horse-race-obsessed media.

Tight races are not breaking open in the final days, an indicator of "the cynicism and apathy that people have." But even with a motivated base, Podhorzer said Republicans are still not where they would like to be heading into Election Day.

"It's really remarkable how many close races there are right now," he said. "And unlike 2010, Republicans are not making inroads into blue territory. In 2010, they were able to win Senate races in Pennsylvania, Wisconsin, New Hampshire and so forth. This time around they may be able to win races like Colorado or others, but they are not changing the presidential map at all. They have their work to do to figure out how to get the map from the way it looks now to a winning map in 2016."

Podhorzer, an engineer of the progressive movement's superior voter turnout machinery, said the battle on election day will be about get-out-the-vote mechanics.

He framed the contest as a test of the GOP's "wholesale GOTV" — paid media and base enthusiasm in a good Republican year — versus the "retail GOTV" of the Democratic coalition that relies on the party's technological advantages and focuses on person-to-person contact and.

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The AFL-CIO's super PAC, Worker's Voice, is part of the field program Democrats are counting on in tough Senate and gubernatorial races in place like North Carolina, Iowa, Wisconsin and New Hampshire.

"The Democrats' retail GOTV has gotten much, much stronger than in 2010, when the base was even more disillusioned," he said. "Democrats will do a better job on retail GOTV, and have more of the personal networks on the ground to pull people out. It's going to be interesting to see how effective that can be."