In the 2010 Massachusetts special election, Scott Brown’s pickup truck was the epitome of his shocking special election upset. In 2012, the Republican senator has jumped whole-hog on the Boston Red Sox bandwagon.

Brown, who has built a successful political brand for himself as an average guy who happens to be a senator, is now using the Red Sox to reinforce that fact. This week, he’s going up with his second radio ad of the campaign focused on the BoSox. The first thanked longtime players Jason Varitek and Tim Wakefield (knuckleballer!) for their long careers with the team, while the second focuses on the team’s iconic stadium, Fenway Park. (Brown’s radio ads have also mentioned the New England Patriots.)

But this strategy isn’t really about Brown; it’s all about his opponent, Elizabeth Warren.

In the ads, Brown makes absolutely no mention of politics, talking only about the history of the Red Sox.

“John Henry, Tom Werner and Larry Lucchino deserve credit for improving what we have rather than starting over somewhere else,” Brown says, noting the stadium’s 100-year anniversary. “Families throughout the years will never forget their first Fenway experience. I know I never will. Go Sox.”

The ad is both a somewhat transparent ploy and a part of a larger — and smart — strategy. And even Democrats acknowledge this.

Former Boston city councilman Larry DiCara (D) said the Red Sox emphasis, much like the pickup truck, plays into Brown’s strengths as a candidate.

“What he has found is he has extraordinary connection to the common man,” DiCara said. “He doesn’t make it up; he really just does it.”

Democratic consultant Mary Anne Marsh added: “No question about it: People are talking about it, and it’s been able to remind voters why they liked him so much the first time.”

Of course, this isn’t the first time the Red Sox have factored into Brown’s campaign.

In the 2010 race, Democrat Martha Coakley was widely criticized for her incredulous response to the idea of shaking hands in the cold at Fenway and also suggested that Red Sox 2007 World Series hero Curt Schilling was a New York Yankees fan. Oomph.

The Red Sox issue isn’t really about what Brown can gain, but what his opponent can lose. Namely: blue collar voters.

“This doesn’t fundamentally change his electability,” said a Democratic strategist granted anonymity to discuss strategy. “This race is all about Elizabeth Warren.”

This strikes us as mostly correct. While the ads certainly don’t hurt Brown, they do put the onus on Warren, a Harvard professor and liberal favorite who has something to prove when it comes to her connection to average voters. The Red Sox are merely a proxy in that battle.

Warren didn’t start out great in this regard, noting in July that her husband was responsible for keeping her up-to-speed on sports teams like the Red Sox. She also couldn’t recall the precise years that the team won the World Series last decade when she was asked at a Democratic forum last year.

But Warren’s campaign more recently, to its credit, has been on the ball (so to speak). It tweeted a photo of her shaking hands — in the cold, no less — outside Fenway Park, and more recently tweeted her prediction that the team would win 96 games this year and that center fielder Jacoby Ellsbury would be the most valuable player.

If you want evidence that this issue matters in the campaign, look no further than those tweets. They are an acknowledgment that she has work to do.

“I hope she’s at Opening Day tomorrow,” DiCara said of the Red Sox home opener. “I’m going to be there. She certainly knows the mistakes that Martha made, and I expect will try not to repeat them.”

(It should be noted that Brown isn’t without sin in this, either: the Huffington Post’s Sam Stein notes today that, in 2001, Brown actually did suggest moving Fenway — a decision his campaign now says would have been a mistake.)

We’ve written before about how his personal appeal is Brown’s saving grace in a very tough state for a Republican — the “Have a beer” factor. Despite some very strong personal favorability numbers, he remains locked in a very tight race with Warren.

In the end, Brown’s Red Sox gambit is about putting pressure on Warren to prove that she can also relate to regular people. And we would expect she will be asked about the Red Sox repeatedly in the days, weeks and months ahead — thanks in part to the marker that Brown’s campaign has laid (and this history of Coakley that looms over the race.)

Tweeting is one thing; responding to questions is a test that Warren hasn’t exactly passed with flying colors yet.

Her ability to answer those questions will be a great indication about whether she can close the “Have a beer” gap. If she can do that, she’ll win.