Negative ads, charges of dishonesty and dwindling time are all setting the tone.
Joining celebrities for fundraising in Los Angeles on Sunday, Obama for the first time needled himself over a poor debate performance. But he declared he had the right focus and "I intend to win."
Romney was in Virginia, trying to bury the memories of his fumbled trip abroad this summer and knock Obama back on national security. "Hope is not a strategy," he said in excerpts of a Monday speech at the Virginia Military Institute.
The campaigns already had eyes on the next debate, the sole faceoff between Vice President Joe Biden and Wisconsin Rep. Paul Ryan, which will grab attention as the Thursday night showdown nears. The election hangs as ever on persuadable voters in fewer than 10 states, with Iowa, Ohio, Virginia and Florida all set for candidate visits this week.
In an election-year display of incumbent's power, Obama on Monday was declaring a national monument at the home of Latino labor leader Cesar Chavez, the United Farmworkers Union founder who died in 1993. Sure to appeal Hispanic voters in swing states, Obama's move comes at the start of a day in which he will later raise political cash at events in San Francisco.
Romney was after the bigger stage of the day.
His foreign policy speech seeks to send tough signals on Iran and Syria and portray Obama as weak for his administration's changing explanation for the deadly attacks on the U.S. consulate in Libya.
"We're not going to be lectured by someone who has been an unmitigated disaster on foreign policy," Obama campaign spokeswoman Jen Psaki said.
Voters give Obama higher marks than Romney on questions of national security and crisis response, and world affairs in general are a distant priority compared with economic woes, polling shows. Romney, though, is seeking to broaden his explanation about how he would serve as commander in chief.
After polls recently suggested Obama had narrow leads in several swing states, the Romney campaign says the race is tightening following his strong performance in last week's debate. To help maintain his momentum, Romney has tweaked his message over the last week, highlighting his compassionate side and centrist political positions.
Beyond his speech, Romney has a Virginia rally scheduled for Monday, then events in Iowa and Ohio later in the week.
Obama displayed a little self-deprecation Sunday night to account for his own showing in last Wednesday's debate.
Taking to the Nokia Theatre stage after some musical stars performed, Obama said the entertainers seemed to have flawless nights all the time.
"I can't always say the same," he said. Everyone in the crowd of thousands seemed to get the joke.
Later in the Los Angeles evening, with actor George Clooney among those attending at $25,000-per-person fundraising dinner, Obama reminded donors that Wednesday's debate had fallen on his 20th wedding anniversary. "There was some speculation as to whether this had an impact on my performance," he said to laughter.
Obama also used that occasion to say he still had his focus on the people he is hired to help as president. Obama said he was reminded of the point by the waiter who spoke to him when he took his wife to dinner over the weekend. After serving the Obamas, the waiter thanked the president for a health care law he said saved his mother's life after she sustained a stroke.
Summarizing his case against Romney, Obama said, "Nothing that my opponent offers will create more jobs, reduce our deficit, grow our middle class, improve our education system, improve our environment or make us safer around the world."
He gave thanks for the help to the wealthy crowd but added, "We're not finished yet and I'm a big believer in closing the deal."
After his California cash rush, Obama was spending Tuesday in Ohio and was expected to campaign in Florida later in the week. He was then to hunker down over the weekend for another round of debate preparation. His second debate against Romney is set for Oct. 16 in New York.
Since the first debate, the Obama campaign has settled on a line of criticism that Romney is dishonest with voters; the Romney camp has returned fire.
Romney, campaigning in up-for-grabs Florida on Sunday, sought to build on the momentum from a debate performance that even Democrats conceded was "masterful." He told a crowd of about 12,000 that he had exposed Obama's shortcomings.
"And next January," he said, "we'll be watching him leave the White House for the last time."