Former Massachusetts governor Mitt Romney is 24 hours (or so) away from winning the New Hampshire primary, his second victory in as many contest in the Republican presidential race. And, Romney is already way ahead in polling in South Carolina, which will hold its primary on Jan. 21.

If Romney sweeps the first three contests, it’s a virtual certainty that his most high-profile opponents will drop from the race — leaving him as the de facto nominee before January ends.

Republican presidential candidate, former Massachusetts Gov. Mitt Romney, campaigns with his wife Ann Romney at Exeter High School in Exeter, N.H., Sunday, Jan. 8, 2012. (AP Photo/Charles Dharapak)

But, a look back at recent presidential history suggests a quick win in the primary season can spell doom in a general election.

As we write in our Monday Fix newspaper column:

In 2008, Sen. John McCain’s victory over Romney in the Florida primary at the end of January effectively ended the nomination fight. (Romney dropped out shortly thereafter and although former Arkansas governor Mike Huckabee remained in the race, McCain was widely regarded as the nominee.)

The Democratic primary fight between then-Sens. Barack Obama (Ill.) and Hillary Rodham Clinton (N.Y.), on the other hand, stretched into June — an extended battle that had Democrats nervous and Republicans gleeful about what it meant for the general election.

And we know how that one turned out.

The 2004 presidential race teaches a similar lesson. After scoring wins in the Iowa caucuses (Jan. 19) and the New Hampshire primary (Jan. 27), Sen. John F. Kerry (Mass.) secured the Democratic nomination.

At the time, party strategists were thrilled with the outcome — the most electable candidate (in their view) had won a quick and resounding nomination fight and was ready to take on President George W. Bush. The reality was something very different as Bush and his political team quickly pounced, defining Kerry as a wishy-washy flip-flopper before the Democratic nominee was able to get out of the general-election gate.

Look further back in history and you find more evidence that longer is better than shorter when it comes to primary fights. Then-Vice President Al Gore swept to the Democratic presidential nomination in 2000 only to lose to Bush. (Bush’s 2000 campaign is something of an outlier to the theory, as he effectively ended it by beating McCain in South Carolina on Feb. 19 but went on to win the general election anyway.) Former senator Robert J. Dole (Kan.) had the nomination in hand by mid-March 1996 but was outspent by far in the spring and summer and went on to lose to President Bill Clinton in the fall.

Make no mistake: Romney will take a win how — and when — he can get it. But, don’t assume winning quickly is necessarily a good thing for the former Massachusetts governor.

“It’s like sitting your starters in football,” Matt Bennett, who was a Clinton administration official, said of a short primary. “The rest may feel good and prevent injury, but it doesn’t steel you for the championship. (Ask the 2009 Colts or John Kerry).”