TAMPA, Fla. (AP) — His convention behind him, Mitt Romney enters the campaign homestretch with a singular goal: convince Americans disappointed with President Barack Obama that the Democrat is to blame for the stagnant economy and that only he can fix it.

“You know there’s something wrong with the kind of job he’s done as president when the best feeling you had, was the day you voted for him,” Romney said, accepting the Republican nomination that eluded him four years ago.

It was the start of a closing argument that aides say will be singularly focused on jobs — the issue on the top of voters’ minds — between now and Nov. 6, as the GOP challenger looks to woo voters who put their faith into Obama four years ago but have soured on him with unemployment stuck at 8.3 percent and the economy sputtering.

Polls show a close race nationally and in key states, ensuring that the hard-hitting, personal attack-filled campaign of the summer will continue this fall, if not escalate.

Romney’s challenges are great. Most voters say they like Obama better than Romney, who struggles to connect with voters. Most also think the president will win a second term.

Romney has fewer paths than Obama as he looks to cobble together victories in enough states to win the 270 electoral votes needed to become president. And his image has been dented after a barrage of negative ads by Obama and his allies that cast the Republican as a heartless job-killing corporate titan.

Still, Romney has a slight edge in surveys over Obama on the question of who would better handle the economy. Between his campaign and allied super political action committees, Romney also is expected to have a significant financial advantage over the president and his backers. And he also has this going for him: Most Americans say the country is going in the wrong direction under Obama.

With polls showing close races or Obama with a slight edge in key battleground states, Romney’s team is weighing whether to try to expand the playing field. They’re considering pouring money into three industrial states Democrats have long won but where Republicans sense opportunity: Wisconsin, Michigan and Pennsylvania. Doing so would force Obama to spend money defending his home turf while potentially giving Romney more electoral-vote paths to the White House.

In the coming weeks, Romney will focus on narrowing Obama’s advantage with women, arguably the most critical constituency this fall, and energizing white voters who lean more heavily toward the Republican challenger than the Democratic incumbent. And all the while, he’ll focus on those who can tip the balance in a close race.

“The people who are really open to voting for me, that I need to get to vote for me to win the presidency are independents and Democrats who’ve been disappointed by the last four years,” Romney told CBS News in an interview this week.

To get them solidly in his camp, Romney will emphasize anew his record in private business as he looks to take advantage of the edge he has on handling the economy.

His advisers say they remain convinced that Romney’s successful career at private equity firm Bain Capital holds the key to the White House despite Obama’s efforts to undercut the key rationale for Romney’s candidacy.

Obama has spent months — and millions — working to sully those credentials by criticizing Romney over his Swiss bank account, his former company’s instances of outsourcing jobs and his refusal to release more than two years’ worth of his own tax returns. The Democrats claim Romney would govern with a profit-at-any-cost mentality that would benefit the wealthy and hurt the middle class.

While the emphasis will be on the economy and jobs, Romney’s team will try to make his case by seizing on related issues like welfare reform and entitlement programs as he looks to pick off support from his target demographic groups.

He will rely on running mate Paul Ryan to help him make the case as the primary critic of Obama. It was a role on display Wednesday when the Wisconsin congressman stood at the convention podium. Ryan also brings Midwestern appeal.

To show his more personal side, Romney will turn even more to his wife, Ann.

A warm, charismatic figure, Mrs. Romney has stepped up her campaigning this week and drew rave reviews with her convention speech Tuesday. Aides say she’ll be on the road as often as possible, partly because the candidate tends to be more relaxed and confident when she’s around. One concern is her health. She suffers from multiple sclerosis, and too much flying or exhaustion can hamper her for days if it’s not managed.

To sell himself this fall, Romney has turned to a group of admakers from Hollywood and Madison Avenue, collectively dubbed “Mitt’s Mad Men” inside the campaign.

Starting Friday, he’ll be able to tap his huge stockpile of general election cash, a chunk of the $177 million he had on hand as August began. Obama’s campaign and party had $127 million available, according to the most recent public data.

Romney’s cash will be spent primarily on television advertising and get-out-the-vote operations in the most competitive swing-voting states: Florida, Ohio, Virginia, Iowa, Nevada, Colorado and New Hampshire. He’s also targeting North Carolina. And he’s looking at making a more aggressive play for Wisconsin, Michigan and Pennsylvania, where outside groups have been on the air for weeks.

Romney will have only a few more opportunities to send a crystalized message to Americans still questioning whether he has what it takes to be president.

To that end, the stakes are high for a trio of October debates.

He’s already been preparing for them by reading heavy briefing books. His advisers view these face-to-face meetings with Obama as the best opportunity for Romney to demonstrate just how he stacks up against the president.