The Democratic favorite is a 37-year veteran of Washington, a loyal and established party soldier who's seeking a promotion to the Senate after a career in the House.
The Republican challenger is a newcomer to national politics, a Harvard-educated former Navy SEAL and second-generation Colombian immigrant who's running against the political establishment.
Gabriel Gomez would seem to be precisely the kind of candidate the post-2012 Republican Party would be looking for, in the kind of race they'd be looking for him in. On paper, it's a dream matchup for Republicans, in the state that -- while heavily Democratic -- vaulted Scott Brown from obscurity to the Senate during President Obama's first term.
Yet with barely a week left in the Massachusetts Senate special election to fill the seat John Kerry vacated when he became secretary of state, national groups on the Republican side are notably silent, even as Democrats pour in outside support for Rep. Ed Markey.
Gomez has already been outspent by nearly $4 million. Republican insiders say Gomez is likely to be swamped, spending-wise, six- or seven-to-one in the final stretch of the race, barring a late cash infusion.
Gomez allies are beginning to sound off about the lack of support they're drawing from national Republican donors, including the outside groups controlled by the likes of the Koch brothers and Karl Rove.
Brad Todd, a top Gomez strategist, said national Republicans appear to have grown too timid after the 2012 electoral wipeout. If they can't support a Latino entrepreneur and military veteran against a career politician, he asked, what are they waiting for?
"This is the world's longest psychotherapy session," Todd said in an interview, referring to the GOP's post-election soul-searching. "We've gotten awful comfortable on the couch. It's time to get up and get in the game.
"The evidence here is that Democrats are scared to lose, and Republicans are scared to win," he added.
Said Lenny Alcivar, another top campaign official and someone who has worked extensively on behalf of Latino Republicans: "Gabriel Gomez is exactly the kind of Republican that so many of us in the Republican Party have been looking for. Grab an oar and get in the boat."
Republican National Committee Chairman Reince Priebus said he believes Gomez offers a template for a brighter GOP future. He said he hasn't given up hope on national donors embracing the Gomez-Markey race as the opportunity it is, saying that it will be a "a late-breaking race."
"I wish we could have 100 Gabriel Gomezes out there in our party," Priebus told ABC News. "I hope for every ounce of help that Gabriel can get in this race. I'd like it to come. I hope it will come."
On the ground in Massachusetts, the clash of biographies hasn't quite defined a campaign that's turned on smaller issues of long-ago tax breaks and tax votes, and one candidate comparing the other to "pond scum."
Still, the race is giving both parties a chance to test-drive messaging and mobilization for next year's midterm congressional elections and beyond. It's also revealing anxieties inside both parties about a still-turbulent political landscape.
On the Democratic side, the clear sense is that the party won't allow itself to witness a rerun of Brown's stunning 2010 victory.