The great bulk of federal spending that isn’t either defense-related or interest on the debt goes to Social Security, Medicare and Medicaid. The first two programs specifically serve seniors. And while Medicaid is often thought of as a poverty program, these days it’s largely about providing nursing care, with about two-thirds of its spending now going to the elderly and/or disabled. By my rough count, in 2007, seniors accounted, one way or another, for about half of federal spending.

And in case you hadn’t noticed, there will soon be a lot more seniors around because the baby boomers have started reaching retirement age…

Which brings me back to those Republican freshmen. Last year, older voters, who split their vote almost evenly between the parties in 2008, swung overwhelmingly to the G.O.P., as Republicans posed successfully as defenders of Medicare. Now Democrats are pointing out that the G.O.P., far from defending Medicare, is actually trying to dismantle the program. So you can see why those Republican freshmen are nervous.

But the Democrats aren’t engaging in scare tactics, they’re simply telling the truth. Policy details aside, the G.O.P.’s rigid anti-tax position also makes it, necessarily, the enemy of the senior-oriented programs that account for much of federal spending. And that’s something voters ought to know.