When President Obama introduced his long-awaited budget last week, most of the focus was on his proposal to reduce payments for future Social Security beneficiaries by using a "chained CPI" calculation. The adoption of the calculation would slow the rate of inflation over time and reduce cost-of-living increases for future beneficiaries.

Now the politics are starting to sink in, and it's scaring Democrats.

The Hill points out that a "growing number" of House Democrats are concerned that the president's proposal "will haunt the party at the polls in 2014."

The New York Times says "opponents on his party's left will make that an issue for Democrats in the midterm elections next year — and perhaps in the 2016 presidential contest."

Responding to the outcry, Democratic strategist Robert Shrum says, "You would think President Obama was proposing to repeal the New Deal."

But perhaps something much bigger and more important is going on here.

Ron Brownstein points out that the complaining among Democrats "suggests that large portions of the Democratic base still don't understand the political and economic dynamics of the party's changing electoral coalition."

He writes:

Obama has already taken a rare step to respond to the budget's generational imbalance with his health care plan, which slows the growth in Medicare spending to fund expanded coverage for the working-age uninsured. Now, the president's nascent cut-and-invest budget approach threads between liberals who would spare all entitlements and conservatives who would retrench investments and entitlements alike.

Instead of hurting Democrats, Obama might actually be creating a foundation to allow the party to hold onto power for decades into the future.