Mitt Romney and Paul Ryan have had some success in obscuring the health care debate by pointing out that Ryan’s proposal does not change Medicare for people currently over 55 years old. This has allowed Republicans to blunt Dem attacks and muddy the waters further by attacking the Medicare savings in Obamacare as cuts to beneficiaries.

But Dems are now going to launch a new offensive hammering home a simple point: Under the Romney/Ryan plan, health care costs for current seniors do go up.

In an interview, Rep. Chris Van Hollen pointed out that the Romney/Ryan agenda constitutes far more than just Ryan’s plan to quasi-voucherize Medicare. It also includes the repeal of Obamacare which, if done successfully, will drive up care costs up for seniors. Van Hollen — who is playing a key role plotting party strategy — says Dems need to broadcast this point far and wide.

Separately, Chuck Schumer is circulating a memo to fellow Dems, advising a more frontal attack on Ryan as a phony deficit hawk.

“This definitely needs to be emphasized: It is simply untrue that the Ryan-Romney plan will have no immediate effect on Medicare beneficiaries,” Van Hollen told me just now. “It will immediately raise the costs for seniors with high prescription drug burdens. It will immediately raise costs for preventive health care services under Medicare.”

Van Hollen noted that repealing Obamacare would get rid of its provision closing the Medicare “donut hole,” that that seniors with high prescription drug costs “will immediately get hit hard under their plan.” Obamacare also eliminated the co-paytments for preventive services under Medicare, to encourage seniors to seek care before their conditions worsen and become more expensive.

“The Romney Ryan plan would immediately increase those costs,” Van Hollen said.

Finally, there is the disputed $716 billion itself — the Medicare savings Obama secured, which are being mischaracterized as a “cut” to beneficaries. Romney’s camp has taken to claiming that Obama “raided” Medicare of this money to pay for Obamacare. But the above cost savings for seniors in Obamacare are partly paid for by that money, Van Hollen notes. What’s more, Van Hollen points out, if the program’s cost goes up, seniors’ premiums — a share of overall cost — go up with it.

Meanwhile, the Romney camp has been presenting Ryan as proof of the GOP ticket’s seriousness on the deficit, but Schumer’s memo presents four points to challenge that. (1) Ryan supported Bush’s deficit-exploding policies. (2) Ryan voted against Simpson Bowles. (3) Ryan urged John Boehner to tank the grand bargain talks. (4) Ryan’s own budget numbers don’t add up.

Says Schumer’s memo: “If we can succeed in showing voters how Ryan is not really a deficit hawk at all — that he prioritizes conservative ideology over balancing the budget — the rationale for his selection is gone, and Romney’s political high-wire act will fail.”

Republicans had great success in 2010 in turning the Medicare debate to their advantage by arguing that Dems were the ones cutting Medicare. But it appears Dems don’t want to be caught off guard this time, and are responding more aggressively right off the mark.