(CNN) -- A raucous news conference Thursday in Mitt Romney's home state of Massachusetts, with pro-Romney demonstrators trying to shout down campaigners for President Barack Obama criticizing the former governor, escalated the November election campaign more than five months before the voting.
Romney, meanwhile, traveled to a shuttered solar panel maker Thursday to focus attention on what he called a symbol of the Obama administration's failed economic policies, as well as cronyism.
"The president took a half a billion dollars of taxpayer money and devoted it to an enterprise that was owned in large measure by his campaign contributors," Romney said of Solyndra, the California solar panel maker that went bankrupt in 2011. "This is serious conflict of interest."
Congressional investigators looking into the Solyndra case have yet to find evidence of the kind of corruption implied by Romney, the certain Republican nominee for president.
However, the loan guarantee of more than $500 million under a Department of Energy program to the company headed by an Obama contributor has become a favorite target for Republican attacks.
Across the country, the Boston news conference by Democrats opened a new front in the Obama campaign strategy by taking on Romney's gubernatorial experience after previously targeting the multimillionaire businessman's background as head of a private equity company.
A crowd of about 30 mostly young, white protesters waved signs declaring "Obama isn't working" and chanted Romney's first name as well as "we want Mitt" and "broken record" as top Obama campaign strategist David Axelrod and several Massachusetts politicians spoke in front of the Massachusetts State House.
Raising their voices over the din, the speakers criticized Romney's record during his four years as governor and referred repeatedly to the demonstrators seeking to drown out their message.
"You can't handle the truth, my friends," Axelrod said to the protesters. "That's the problem. If you could handle the truth, you'd quiet down."
At one point, Axelrod noted that polling shows Romney trails well behind Obama in Massachusetts, calling that an indictment of Romney's record as governor.
"These may be the only voters, right here, for Mitt Romney in Massachusetts," Axelrod said, gesturing to the demonstrators. "It's a harsh judgment from people who know him best."
Axelrod also said Romney's business background at Bain Capital failed to prepare him for government leadership, and his experience in the governor's office for one term showed Romney failed to deliver on promised economic development.
"He was a drive-by governor here on his way to running for president of the United States," Axelrod said, later adding that Romney "played a shell game in order to say that he was making progress, and then he left a mess on the doorstep of the next governor."
Axelrod repeated a consistent theme of the Obama campaign -- that Romney' s motive in business was making the biggest private profit for himself and investors, rather than working for the overall public good.
Citing what he and other speakers called problems from Romney's term as governor, including lagging employment and increased debt, Axelrod said making profits was "fine, but it's not a prescription for leadership, as we saw in Massachusetts."
"That's what happens when you try to transfer those values and those principles into the governance of a state or country," Axelrod said.
Before the Democratic event, state Republicans held their own news conference in the same spot, cheered by the demonstrators, who arrived by bus.
Dan Winslow, a Republican state representative, said that under Romney, Massachusetts "created more net new jobs in the state than President Obama has created in the last four years in the United States."
Massachusetts House Minority Leader Brad Jones said Obama lacked a successful record as president, so his campaign was focused on attacking Romney.
"If he had respectable job growth, he'd be running on his own record instead of criticizing others," Jones said.
In California, Romney's visit to the Solyndra building outside San Francisco was cloaked in secrecy, with the destination unannounced until shortly before the candidate and reporters arrived at the site.
A Romney adviser said the campaign had concealed the event location for fear the Obama administration would somehow prevent them from staging it. Romney told reporters his campaign had wanted to head off any efforts by his rivals to keep him from speaking.
"This building, this half a billion-dollar taxpayer investment, represents a serious conflict of interest on the part of the president and his team," Romney said. "It's also a symbol of how the president thinks about free enterprise. Free enterprise to the president means taking money from the taxpayers and giving it freely to his friends."
Obama administration officials have called the failed Solyndra loan a disappointing result in their ongoing support of innovative technology. They vow to continue investing in clean energy.
"Over the course of this first term, we will have doubled the use of renewable energy in this country," Axelrod said Thursday in an interview to air on CNN's "John King, USA."
He added Romney was simply using the Solyndra stop as a "diversion" from recent attacks against Romney's corporate career in private equity
"One thing the president never did was buy a company, load it up with debt, bankrupt that company, and walk away with millions of dollars while the creditors and the workers were left holding an empty bag," Axelrod said, referring to Romney's former firm, Bain Capital.
Meanwhile, the Republican National Committee released a video Thursday that uses Solyndra to bolster its message that Obama is a bad job creator.
RNC Chairman Reince Priebus said Solyndra exemplifies the president's job creation record.
"I guess we can't be surprised with the economic results we have received over the past three years. Barack Obama has never run a business. He's never met a payroll and hasn't created a single job. The only thing he's ever managed is his personal narrative," he said in a written statement. "America needs Mitt Romney in the White House because he's spent time in both the private and public sector and understands how to get Americans back to work."
A survey released Thursday indicated that Romney and Obama are statistically tied in three of the general election battleground states that Obama won in 2008.
The NBC News/Marist poll showed a neck-and-neck race in Colorado, Iowa and Nevada, where voters said the economy was by far their top issue heading toward Election Day.
Romney's record as governor also came under scrutiny in a video released Thursday by the Obama campaign that features Democratic officials from Massachusetts.
In the video, mayors and state legislators compare Romney's campaign promises to results, slamming Romney for not developing solutions to an outflow of manufacturing positions.
"We knew that we were losing manufacturing jobs, and he never found any solutions to try and figure out how we were going to keep them," Jeffrey Sanchez, a state representative, says in the video. "By the time Mitt Romney left office, we were 47th in the nation in terms of job growth."
That statistic, cited frequently by Obama's campaign, is accurate, though the nonpartisan PolitiFact rates the full assertion as only "half true," noting that it's a stretch to entirely blame Romney (or any governor) for a state's jobs numbers.
The video also includes claims by state Rep. Jay Kaufman that Romney hurt middle-class families by raising fees, rather than taxes.
"What we heard from Mitt Romney during the campaign was a 'no new taxes' pledge, but what he found very quickly during his term in office was that he couldn't deliver on any services without having sufficient resources, so he raised our taxes by raising our fees," Kaufman says in the video.
Romney's record on taxes was similarly hit by fellow Republicans during the GOP primaries. A CNNMoney analysis of his record determined that he cut select taxes while in office, and proposed some new tax cuts that didn't pass the legislature -- like a 0.3 percentage point reduction in the 5.3% state income tax rate.
But he also had an obligation to balance the state's budget every year, and when he came into office, he was facing a big deficit that he plugged using a mix of spending cuts and revenue increases, including the fee increases.
Carl Sciortino, another state legislator featured in the Obama video, said those fees hurt working families, who "were paying more under his administration."
Sciortino says in the video that Romney's campaign promises reflect the GOP presidential candidate's current campaign.
"There are times when I watch Mitt Romney saying the exact same things now that he said here in Massachusetts in 2002 in a robotic way that is completely hollow," Sciortino says. "It didn't work here, so I'm not sure why he thinks it would work nationally."
CNN's Kevin Liptak and Gabriella Schwarz contributed to this report.