The news that Senator Clinton, having gone zero for four over the weekend in caucuses or primaries in Maine, Louisiana, Nebraska, and Washington, is changing campaign managers is a sign that Mrs. Clinton recognizes that something is wrong with her campaign that needs correcting. What Mrs. Clinton really needs, though, isn’t new campaign management but a new message, one that sharpens the contrast between her and Senator Obama. This wouldn’t be that difficult; the distinctions are already there, they just need to be brought into focus.

On the foreign-policy front, Mr. Obama says he would meet, without preconditions, with the leaders of Iran and Cuba. When Mr. Obama made the offer, Mrs. Clinton’s campaign derided it as a rookie mistake in which Mr. Obama would offer dictators a prestigious platform in return for nothing. The Clinton campaign put out a press release on the issue in July, headlined, “Vilsack Challenges Obama To Explain When He’d Meet With Rogue Leaders.” Since then, though, the Clinton campaign has mostly dropped the issue. Another distinction is Mrs. Clinton’s vote empowering President Bush to impose tougher sanctions on Iran, including in respect of the Iranian Revolutionary Guard. Mr. Obama, in a serious error, voted against it.

On foreign policy, Mrs. Clinton could explain to Democratic primary voters that the likely Republican nominee, Senator McCain, will be running as a war hero who supported the surge in Iraq. The Democrats for years campaigned as the party of weakness on foreign policy, which helped cost them the presidency. President Clinton started to turn that around with military interventions in Bosnia and Kosovo and with cruise missile attacks in Iraq, Afghanistan, and Africa. Mr. Obama would turn the party back toward the wilderness into which it was led by Senator McGovern. Mrs. Clinton, a member of the Armed Services Committee who has been to Iraq and to Afghanistan, knows that sometimes military force is needed. As the senator who represents New York, she saw the consequences of the September 11, 2001 terrorist attacks firsthand, and knows that the enemy isn’t just some figment of Vice President Cheney’s imagination.

On taxes, Mr. Obama has pledged a payroll tax increase for Social Security that, together with the expiration of many of the Bush tax cuts, would make the largest tax increase in American history. Senator McCain is going to be campaigning for the extension of the Bush tax cuts and against the payroll tax increase. Again, Democrats ran candidates for the presidency for years who promised to raise taxes on working men and women. Those candidates lost, and so will Mr. Obama once the Republicans spend tens of millions of dollars on campaign commercials making sure everyone knows he is promising the biggest tax increase in American history — a tax increase so big even Hillary Clinton is against it. It was only when Bill Clinton promised a middle class tax cut that the Democrats finally won back the White House.

On another key domestic issue, the welfare reform enacted under Mr. Clinton, Mrs. Clinton is on record saying it was a good thing. Mr. Obama is reported to have been “deeply apprehensive” about the law that has done so much to shrink the rolls, enlarge the workforce, and reduce dependency. On crime, Mrs. Clinton has come out against letting thousands of convicted drug dealers out of prison and onto the streets by applying retroactively new sentencing guidelines that equalize treatment of crack and powdered cocaine offenders. Mr. Obama favors releasing these criminals. Again, who is going to fare better in a race against a Republican armed with tens of millions of dollars to spend on negative campaign commercials.

This is not an endorsement in the Democratic primary. We have differences on policy with both candidates and see many virtues in each. It may turn out to be that what ails the Clinton campaign is the candidate herself and that Americans are just ready to move on from both Clintons and Bushes. But if Mrs. Clinton has a hope of salvaging her campaign, an issue-based approach on foreign policy, taxes, crime, and welfare has the best chance of beating Mr. Obama, turning Mr. Clinton from a sideshow or distraction into an asset, and providing a platform that has at least a chance of prevailing in a general election. The platform is there in planks that Mrs. Clinton has already stood on. All that remains is for the senator from New York to press the substance of her case.