Barack Obama very much wants to keep his job as president, and several Republicans very much want to replace him. But who wins next year may depend on how many of the American people have jobs -- or don't have jobs -- when Election Day comes around.

More than 9 percent of would-be American workers are officially jobless today, and millions more have either given up the search or can get only part-time jobs.

Indications are that unemployment could be the decisive issue in 2012. Unemployed voters and sympathetic friends and family of the unemployed likely will take their strong feelings about our economy into the voting booth.

Obama, already running for re-election, says Congress should "do something" to promote jobs. So you can guess what's on his mind: more federal stimulus spending on various infrastructure projects around the country. He also wants to extend a reduction in the payroll tax that funds Social Security.

"These are commonsense ideas -- ideas that have been supported by both Democrats and Republicans," he said in a recorded address. "The only thing holding them back is politics."

Actually, the bad track record of "stimulus" spending is holding back Congress from approving more stimulus. We're still waiting for the jobs the first stimulus was supposed to create.

Republican hopeful Gov. Rick Perry of Texas, meanwhile, is understandably campaigning on his state's strong job growth. He says he knows how jobs are created, and that he will seek to replicate that nationwide.

GOP candidate Rep. Michele Bachmann of Minnesota has her own prescription. It includes things such as reducing the corporate tax rate and capital gains taxes to spur investment, as well as providing tax advantages when job-creating businesses buy equipment. She also wants to roll back costly ObamaCare and its massive regulations.

Republican former Massachusetts Gov. Mitt Romney favors ending ObamaCare, cutting spending, opening more foreign markets to U.S. goods and boosting America's energy independence.

Obama's job policies -- which amount to more government intervention -- aren't working. But his GOP opponents needn't think that alone will win one of them the White House. They will have to convince voters that their smaller-government plans will work. We'll know soon enough how persuasive they are.