In relatively good times, a first-term president's wide array of powers can force his challenger to shift from issue to issue, hoping to find a gap in the incumbent's armor. This year, that scenario is practically turned on its head.
Romney is the play-it-safe candidate, rarely straying from his jobs-and-economy talking points and sharply limiting encounters with national reporters. He took six hours Friday to offer a short and carefully worded comment that criticized Obama's new immigration policy for not providing "a long-term solution."
Romney didn't say whether he would overturn it if elected. But by noting "it can be reversed by subsequent presidents," he might have sown doubts in the minds of some young illegal immigrants studying the policy.
Obama looks like the bigger risk-taker. He doesn't have many options.
He is constrained by a complex, interrelated, and frail global economy, and by a Republican-run House. Together, they severely limit his ability to influence the struggling U.S. economy, which Obama says needs more investments in education, renewable energy sources, and other areas.
With a single action, however, Obama can allow gays and lesbians to serve openly in the military; direct Catholic-affiliated employer insurance plans to cover contraceptives; and protect hundreds of thousands of young illegal immigrants from being deported.
He took that last step Friday. It delighted many Hispanic groups and prompted Republican officials to grouse more about the process he used than the actual policy.
Democrats enjoy a hefty edge among Hispanic voters, and some GOP strategists fear Romney is widening the gap.
In the primaries, Romney criticized one rival, Texas Gov. Rick Perry, for granting in-state college tuition to illegal immigrants. The former Massachusetts governor also distanced himself from Newt Gingrich's call for making clear that the United States would not deport illegal immigrants who have led stable, crime-free lives for many years.
"This is the right thing to do," Obama said in the Rose Garden as he outlined the new policy Friday.
Sidestepping Congress, where immigration proposals have languished for years, Obama acted to make illegal immigrants immune from deportation if they were brought to the United States before they turned 16 and are younger than 30, have been in the country for at least five continuous years, have no criminal history, and graduated from a U.S. high school, earned a GED diploma or certificate, or served in the military.
Millions of people in the United States, especially younger voters, rallied to Obama's 2008 campaign because they saw it as a crusade giving voice to those weary of the Iraq war and falling economic opportunities. Democratic strategists hope to reignite some of that enthusiasm.
Obama effectively ended the military's "don't ask, don't tell" policy in 2010 by persuading Congress to enact the change, which activists warned he could do on his own if the lawmakers balked. He won more praise from gay activists last month when he embraced same-sex marriage, even if the move was largely symbolic. The bigger legal step was his 2011 decision not to enforce a federal law defining marriage as between a man and a woman.
If the economy were humming, Obama might not need to do big and bold things. But a national unemployment rate of 8.2 percent forces him to take some chances.
That's what he did Friday, briefly stealing attention from the start of Romney's five-day bus tour, whose theme is clear: jobs, jobs, jobs.