Two months ago, Republicans in Massachusetts had high hopes of repeating their 2010 special election miracle and picking off another Democratic Senate seat. Fresh off a victory in the Republican primary, Gabriel Gomez, a successful businessman and former Navy SEAL, trailed Democratic nominee Rep. Ed Markey by just four percentage points, according to one survey. Many saw a parallel between this race and the one that propelled former Sen. Scott Brown (R) into Congress three years ago. Not unlike Brown and his infamous pickup truck, Gomez even had his own blue collar prop: An olive bomber jacket.

Since then, however, Gomez hasn't even come close to matching his early showing. Two different polls in the past week gave Markey a 20-point lead, while others in the past month showed him up by between seven and 12 points. Not one survey of the race has shown Gomez in the lead, and even his latest internal poll had him down by seven points.

For all its initial fanfare, Gomez's campaign never seemed to gain momentum. Gomez's party has been bogged down by an unfavorable political climate and his campaign has repeatedly been outdueled by Markey's well-funded operation.

By contrast, in 2010, Brown was buoyed by a sour economy and by a mounting backlash against President Obama, allowing him to capitalize on the same disappointment with Washington that would hand Democrats a huge November "shellacking" later that year. Now when voters "see Congress not working, the majority of [them] see Republicans," a Democratic strategist, Mary Anne Marsh, told Politico.

Brown also benefited from facing an opponent, Attorney General Martha Coakley, whose campaign failures and general aloofness led to an implosion so astounding it spawned a snarky, eponymous term for defeat in the face of almost certain victory: Coakleyed.

In the current special election campaign, Markey has avoided the self-destructive gaffes that doomed Coakley and has remained on top throughout. With the race heading into the home stretch, Massachusetts' largest newspaper, The Boston Globe, endorsed Markey last week, calling Gomez's policy positions a "work in progress."

Perhaps most prominent among those issues "in progress" was Gomez's handling of questions about reproductive rights.

With national Democrats again decrying a Republican war on women this year, Gomez suggested he would back a Supreme Court nominee in favor of overturning Roe v. Wade. He also avoided answering a question about employer funding for birth control, prompting the Markey campaign to cut an ad labeling Gomez as indifferent and uninformed on women's issues.

A recent Globe poll showed Markey with a 26-point edge among female voters.

Markey has also benefited from a slew of Democratic heavy-hitters turning out to support his candidacy. President Obama, Michelle Obama, former President Bill Clinton, Vice President Joe Biden, and Sen. Elizabeth Warren (D-Mass.) all stumped for him.

As for Gomez? He got a late endorsement from Scott Brown.

On the financial front, Markey has raised millions of dollars more than Gomez, who has meanwhile faced lingering questions about a $281,500 tax deduction he claimed on his $2.1 million home.

"For a while there, it looked as if Gabriel Gomez might be the next Scott Brown," The Washington Post's Aaron Blake and Sean Sullivan wrote of that tax break. "Today, he's looking more like another Massachusetts Republican: Mitt Romney."

With the election one day away, Gomez's prospects of victory seem dim, though he's hardly finished.

Low voter turnout, a hallmark of special elections, could work in his favor. Voters have requested 13,000 fewer absentee ballots than the number issued ahead of the 2010 special election. Elections with low turnout are typically more volatile, meaning Gomez could wipe out the deficits shown in recent surveys, or at least make the race more interesting than those polls have suggested.

That's not to diminish what's patently evident: Markey is a clear favorite heading into election day. But as Massachusetts proved just three years ago, anything can happen in a special election.