Two blocks west of Mitt Romney’s headquarters here, his campaign has opened a new front.

Since clinching the Republican nomination two months ago, Romney advisers have significantly stepped up their digital campaign, hoping to catch up with President Obama in an arena he dominated in 2008. Romney has hired data analysts and mobile-app developers from places including Google and Apple, unwilling to concede the traditionally liberal-leaning Silicon Valley talent pool.

Romney aides acknowledge their online and mobile efforts are unlikely to surpass Obama’s in scale. The president’s reelection campaign spent $26 million on online advertising through May 31 — far more than Obama had spent at this stage in 2008, when he was revolutionizing the use of technology in politics, and at least four times more than the Romney campaign. By one measure, Obama delivered more than 800 million paid Internet ads in February alone — six times more than the entire Republican primary field.

Yet even if they are destined to be outspent and outmanned, Romney’s advisers contend that they can outsmart their counterparts in Chicago in a few important ways — including engaging their supporters online more intensely than Obama’s campaign is mobilizing his, and using digital data to identify and woo independent voters in the narrowest demographic groups in states where a few percentage points could decide the election.

A number of private-sector consultants and past Obama advisers say the technological playing field is leveling.

“They both have an infinite amount of money. They both are doing roughly the same things. I don’t see any reason to believe why they won’t be even on the technology front, said Jim Gilliam, a founder of NationBuilder, a tech firm that helps political candidates build social networks.

In certain respects, the two campaigns’ efforts mirror each other’s, at least on the surface. Both have interactive, dynamic Web site home pages as well as state- or issue-specific pages. They both churn out a flurry of campaign propaganda — videos, tweets and informational graphics — and have online stores selling schwag, such as T-shirts and bumper stickers.

Both also have sophisticated advertising campaigns built around search terms on Google and YouTube. And they have successfully mobilized partisans to make online donations at important moments — for Obama, his decision to support same-sex marriage; for Romney, the Supreme Court ruling upholding Obama’s health-care law.

Still, there are differences. On Facebook, where the campaigns can interact with supporters and extract valuable information from them, Obama has 27 million supporters, while Romney is far behind with just 2 million.

The Romney campaign is building advantages, however. Where 5 percent of Obama’s fans are engaging on Facebook at a given time — for example, by liking, commenting on or sharing a post or a video — 32 percent of Romney’s are engaged.

Another difference: Where Obama’s campaign has engineered its digital products in-house — most notably, a “dashboard” that debuted in spring and enables supporters to connect with the campaign, keep up with news, volunteer and give money — Romney’s campaign is outsourcing much of its development work to private-sector digital firms.

Romney advisers contend that by turning to outside engineers, they can tap into fresh innovations in the free market and “glue” them together in Boston.

“It’s the hubris of the Obama campaign — this belief of, ‘Trust us, we know best,’ ” said Zac Moffatt, the Romney campaign’s digital director. “I disagree with that. I believe the marketplace is smarter. . . . We don’t want to create the next Google. We want to leverage Google to be better to win the presidency.”

Making light of the competition, Moffatt quipped in a recent interview, “I don’t think IBM wakes up every morning and thinks, ‘How do I get in touch with Obama’s data scientist?’ ”

And he tried to pop what he sees as the Obama digital balloon.

“What makes them the best?” Moffatt asked. “Because they’ve told you they’re the best? . . . Have you ever actually used on your iPhone? It doesn’t meet the user experience expected from a team that has been planning for four years. It has 37 things drop-down just in the menu bar.”

Romney’s mobile app has had issues, too. It initially misspelled “America” in Romney’s slogan on the title page; the campaign corrected the typo.

Romney’s advisers are trying to debunk the idea that the tech community broadly supports Obama. “The start-up entrepreneurial world is less all-Democrats, all-the-time than you’d think,” Moffatt said, noting that he traveled to Silicon Valley last month to meet with entrepreneurs at Google, Facebook and Twitter.

Moffatt’s evidence: his growing team. The Romney campaign had 87 staff members when the primary campaign ended two months ago. Today, Moffatt has more than 80 staff members in the digital department alone. The team was annexed from campaign headquarters, taking over the second floor of the brick building a couple of blocks away that houses the Massachusetts Alcoholic Beverages Control Commission.

Romney’s digital army sits at long tables and toil on laptops and iPads, taking occasional breaks lounging in beanbag chairs. Against one wall are the bikes they ride to work; tacked to another, enlarged maps of general election battlegrounds such as Ohio, Iowa and Nevada.

There are similarities to Obama’s vaunted team of Web wizards. That is what Romney’s advisers say they want people to see.

In 2008, when the Obama campaign was building its social network to enable volunteers to organize themselves and donate, Sen. John McCain (Ariz.), the Republican nominee, had just four digital staff members and paid little attention to the emerging technologies.

There was no GOP digital road map for Romney to inherit, so Moffatt — a 32-year-old whose first campaign was New York Mayor Michael Bloomberg’s 2001 mayoral race and learned to crunch behavioral data on President George W. Bush’s 2004 reelection campaign — charted one.

The Romney campaign, like Obama’s, has been studying consumer behavior to target voters who might not see television advertisements. It commissioned a poll of voters in Florida and Ohio to see how many watch television and, for those who don’t, what kind of Web sites they frequent. Moffatt won’t say what the poll found — “That’s the secret sauce,” he said — but his digital analysts are tailoring marketing schemes to reach them.

Moffatt is particularly dismissive of the Obama campaign’s Facebook efforts, repeatedly accusing the Obama campaign of touting “vanity metrics,” such as its 27 million followers, when so few of them are engaged.

“They are constantly promoting vanity metrics — not actionable metrics,” he said. “It is like going to the gym just to work on your biceps.”

The Obama campaign declined to comment, citing a policy not to publicly discuss digital strategy. But privately, Democrats close to the campaign were critical of the Romney efforts. They said Obama has a larger proportion of small-dollar online donations than Romney. And regardless of engagement statistics, they said, Obama remains solidly ahead of Romney in net supporters on Facebook. They said both metrics were indications of Obama’s superior grass-roots organization.

Romney’s campaign officials do not deny Obama’s advantage. Because of the sheer volume of Obama’s Facebook fans, every adult American on Facebook — there are about 160 million of them, according to Facebook — can be presumed to be “friends” with an Obama fan. That means Obama’s messages could wind up on the Facebook timelines of virtually everyone.

The Romney campaign had a major test of its catch-up effort late last month when the Supreme Court ruled on the Affordable Care Act. In the 72 hours after the ruling, Romney launched about 60 different initiatives to reach out to supporters online, either with videos or display advertising or tweets.

Over those three days, Romney raised more than $6.7 million online from more than 70,000 donors, Moffatt said. About 70 percent of them were first-time donors, he said, creating a new pool of supporters to tap down the road. The average donation was less than $100, and the median $25.

Perhaps more important, in the Romney campaign’s “core states,” where it has field staff, supporters were 60 percent more likely to be engaged online than in nontarget states. In Florida, for instance, 38,000 people interacted with Romney’s Facebook page Thursday, Moffatt said.

This even surprised some Republicans.

“We didn’t necessarily think, until the health-care decision last week, that there would be a grass-roots outpouring for Mitt Romney. It wasn’t the style of the campaign or the candidate,” said Patrick Ruffini, a GOP digital strategist. Now, he said, “President Obama could be in a good deal of trouble financially and organizationally.”

Amy Gardner and T.W. Farnam in Washington contributed to this report.