Democratic Senator Mark Begich of Alaska is embroiled in one of the toughest reelection campaigns in the country, and control of the Senate could be at stake.

So he’s going to ramp up his push for a proposal that is treated as marginal inside the Beltway, but could nonetheless prove to have appeal even in a deeply conservative state: The proposal to expand Social Security.

As the Alaska Senate race hits its final, frenzied stretch, the Begich campaign is set to roll out a new set of policy prescriptions that are focused on older voters — which you can read about right here. Central to this push is Begich’s proposal to shore up Social Security’s finances, but in a way that would permit an expansion of benefits to certain groups of seniors.

Begich is set to hold two town meetings with seniors today, at which he will push the proposal, and his campaign confirms that it will be a key component of his message in the final stretch of the race. Begich spokesman Max Croes emails:

“Begich firmly believes we need to expand Social Security benefits, not cut them, and he’s committed to sharing this view and standing up for Alaska seniors on the campaign trail, as he has in the Senate. In the coming weeks Begich will make the contrast with his opponent very clear. Begich’s opponent, Dan Sullivan, believes Alaska’s seniors should have to pass a test to receive the Social Security benefits they’ve spent their life contributing to and supports raising the retirement age.”

Begich’s proposal would lift the existing payroll tax cap so the program no longer exempts wages above $117,000, bringing more money into the program. As Dylan Matthews has explained, this would shore up the program’s finances over time, and it would also make it possible to increase benefits across the board. That alone would help lower income seniors. But the Begich proposal would also mean a larger increase in benefits for groups such as the spouses of deceased seniors — most commonly women — in keeping with changes in the economy that have made it harder to get by on one income. Disabled seniors would also get a larger rise in benefits, and more benefits would be available to the children of deceased and disabled seniors.

The proposal adopts a measure indexing for inflation that’s designed to deal with the reality that seniors spend more on things — such as medicine and housing — whose costs are increasing rapidly. This is in contrast to the “chained CPI” proposal that many inside the Beltway (Democrats included) have pushed that would index benefits to inflation in a way that would amount to a benefits cut.

The goal: Sharpen the contrast with GOP opponent Sullivan in the final days of the race. Sullivan has signaled an openness to means testing and raising the eligibility age.

Proponents of expanding Social Security have long argued that Democrats should campaign hard on expanding social insurance programs — at a time when stagnating wages and the lingering damage of the Great Recession have increased anxieties about financially unsustainable retirement – as a way to maximize traditional Democratic Party advantages on difficult political turf. The idea is that it’s good politics to push for an expansion of a hugely popular program that has been central to the Democratic Party’s identity for many decades, particularly at a time when Dems are facing a stiff political headwind and grappling with extremely difficult election fundamentals.

Begich has long tried to draw this contrast around this issue. “Are we for or against helping seniors have a dignified life in their later years? I’m for that,” Begich recently said, by way of spelling out this contrast. “They would reduce the benefits of seniors. I’m working to make sure benefits are preserved and increased to reflect the costs seniors face.” Now Begich’s campaign says he will amplify this message in the final days of the race.

In an interesting twist, this issue has a local angle, too. The Begich camp notes that Alaska seniors pay higher costs for things like food (which is shipped in from afar) and heating, which makes a Social Security benefits hike for them particularly important. This is a point Begich will likely amplify, too. With Sullivan pushing to make the Senate race turn on Obama’s unpopularity, Begich’s chances may turn on his efforts to localize this race, by speaking directly to regionally-specific concerns of Alaskans. Interestingly, Social Security could fit this bill.

Given that the polling averages show Sullivan with a slight lead, it’s anyone’s guess whether this will be enough to help Begich survive. But it’s notable that he believes campaigning on this could be a winner in such a conservative state, and as such, how it plays bears watching.