By David Nather, CQ Staff

In four years, Howard Dean went from high-decibel presidential candidate — and mobilizer of mostly young, liberal voters — to low-key, nuts-and-bolts chairman of the Democratic National Committee, telling his party to broaden its appeal by talking to the red states again.

Now, he has no official platform in politics or government.

So the former Vermont governor is trying to return to his role as a mobilizer of mostly young, liberal voters — and anyone else who will listen — with a book on health care that stresses the importance of including a government-run health plan in the package Congress is starting to consider.

The proposal, typically called the public plan option, is one of the most controversial elements of this summer’s blossoming health care debate, and it is being rejected by Republicans and some centrist Democrats. But in the book, “Howard Dean’s Prescription for Real Healthcare Reform,” Dean says President Obama and congressional Democrats shouldn’t compromise the public option away just for the sake of bipartisanship. Without it, he says, the private health insurance system will have no incentive to reduce costs and eliminate the gaps in patients’ coverage.

The point of making the case for the public option, Dean says, is “to let the American people know that they should have a choice, and the choice should be up to them, not the government and not the insurance companies.”

The book highlights the role Dean — a physician who had a family practice with his wife, Judith Steinberg, before entering politics — is trying to carve for himself since his term as DNC chairman ended in January. His “50-state project,” which set up party operations in heavily Republican states to make sure no state got written off, helped revitalize the Democrats’ fortunes. But he had fought with then-Rep. Rahm Emanuel , now Obama’s chief of staff, over strategy and is now out of power; he had hoped to become Obama’s Health and Human Services secretary, but was passed over.

Dean consequently is free to promote liberal priorities without being forced to hold his tongue. When Christopher J. Dodd of Connecticut, another former DNC chief who’s one of the Senate’s leading health care negotiators, signaled a willingness last week to consider alternatives to the public option, Dean maintained just a sliver of the diplomacy he used to exercise as party chairman. “I think Sen. Dodd is doing the best he can under the circumstances,” Dean said, but “at the end of the day, bipartisanship doesn’t do us any good if we end up with a crummy bill.”

In substance, Dean’s ideas for a health care overhaul don’t differ much from Obama’s. His main twist is to suggest simply giving medical care to all Americans younger than 30 and subsidizing insurance for older adults who can’t afford it — a way of bypassing Obama’s doubts about whether it’s fair to require all Americans to buy medical coverage.

The real question, though, is whether Dean’s views will make a difference. Some liberal leaders are cheering him on, but those who have to answer to a broader spectrum of interests are lukewarm. “We need everybody,” says Ralph Neas, chief executive officer of the National Coalition on Health Care, which includes labor unions, business organizations, consumer groups and retirement funds. “That’s not to say everybody will agree with every position he takes. But his expertise, his experience and his commitment will be respected by everybody.”

Still, others say Dean’s return to health care policy brings his political career full circle, since he was always more interested in public policy than in political management. “I think public policy is his real love,” says Harold Ickes, who was a Clinton White House aide and a senior adviser to Hillary Rodham Clinton ’s presidential campaign. “Doing what he’s doing right now puts him right in the middle of a national debate, and he has something to add to that debate. And he has a following that can be mobilized.”

Dean notes, “The reason I got involved in politics in the first place was to make sure we have universal health care.” And he’s not just aiming his book at young progressives, he says: “I see myself as speaking to a broader audience. Anyone who’s interested in health care, I want to talk to them.” Now, he’ll have to hope there’s a broader audience that wants to listen.