THE CANDIDATES ARE off and running in the short sprint to the April 3 special election primary to fill the state Senate seat vacated in late January by Linda Forry. The race is sure to generate some excitement for political junkies, but it could also be seen as grounds for some unease and misgivings about our electoral system.

That’s because a case can be made that the last honest election for that Senate seat took place during Richard Nixon’s first term when a 36-year-old South Boston state rep named William Bulger won the slot.

The races for the seat since then have not been crooked in any scandalous way that involved law-breaking or rigged vote tallies. Their departures from the best of democratic norms have been far more prosaic, and so common that they are no longer the exception but the rule.

In the nearly 50 years since Bulger won the seat as an up-and-coming figure on the political scene, every opening in the Senate post has been filled via special election.

Special elections are called when a vacancy occurs outside the standard schedule of elected terms, usually because an official resigns but occasionally because of an officeholder’s death. Special elections, which take place outside the regular election schedule, are open to all. But in practice, they represent a thumb on the scale favoring insiders.

The short notice – there will be just 69 days from Forry’s announcement last month that she was resigning until the April 3 primary – gives a big advantage to those who already have wide name recognition and an established campaign apparatus and war chest. What’s more, special elections offer current officeholders the added perk of not having to give up their current post in order to seek a higher one.

Instead of the old adage “up or out,” it’s a no-risk shot at an open seat, where the consolation prize for losing is retaining one’s current office.

It might be one thing if special elections were an unusual occurrence. But in contests for open legislative seats in Massachusetts, which represent the best chance for fresh blood on Beacon Hill, special elections have become anything but rare sightings.

As election reform advocate Paul Schimek documented last fall in CommonWealth, over the last two decades, 25 percent of the 199 open contests for House seats and nearly one-third (32 percent) of the 56 open contests for Senate seats have been special elections. Turnout in those races was 20 percent lower in primaries compared with regularly scheduled primaries, and 73 percent lower in general elections.

“Yes, it is something that is of concern,” said Pam Wilmot of Common Cause Massachusetts, who called it “rather shocking” that so many open-seat races are being decided by special elections. “But it isn’t clear to me that there is a better alternative,” she said, pointing to the options of leaving seats vacant and districts being without representation or a system by which someone is appointed to fill the remainder of a term.

According to Schimek, half of all states don’t use special elections to fill legislative vacancies and instead employ various systems for appointing someone to fill the vacancy. While that hardly seems to keep faith with democratic principles, Schimek suggested that simply keeping some seats vacant might not come at an enormous cost to representative government.

He wrote that nearly 39 percent of the state’s legislative special elections since 1997 have been held in even-numbered years – the same year as the regularly scheduled state elections for the two-year terms. He suggested that we might at least modify the procedures to leave open seats vacated in election years, particularly since the Legislature holds no formal sessions past July in those years.

Special elections also come at a considerable cost to taxpayers. Boston officials say it will cost the city about $245,000 to carry out the Senate special election primary and final election for the seat Forry vacated.

For now, though, Senate rules call for a special election anytime a vacancy occurs up until April 1 of an even-numbered year.

For the First Suffolk seat, which covers South Boston, Dorchester, Mattapan, and a slice of Hyde Park, that’s become old hat.

It happened in 1996, when Steve Lynch, then a state rep from Southie, won the seat after Bulger resigned to take the president’s job at UMass. It happened in 2002 when Jack Hart, then the Southie state rep, won the seat following Lynch’s win in a race for Congress (also in a special election). It happened in 2013 when Forry, then a Dorchester state rep, won a special election following Hart’s resignation, and it’s playing out again now after Forry resigned to take a job in the private sector.

After meeting this week’s nominating signature deadline, state Rep. Nick Collins of South Boston (who came up short to Forry in the 2013 special election) and Rep. Evandro Carvalho of Dorchester are charging hard toward their showdown in the April 3 Democratic primary. According to the Dorchester Reporter, two other candidates, perennial office seeker Althea Garrison and Donald Osgood Sr., have submitted signatures to appear as unenrolled candidates in the general election on May 1, but the winner of the Democratic face-off between the two reps will be the prohibitive favorite to capture the seat.

Special elections provide a tilted playing field – though no ironclad guarantee for those who are wired well to run, said Peter Ubertaccio, a political science professor at Stonehill College.

“The mechanics of these special elections do favor insiders,” Ubertaccio said. “Having said that, if insiders always benefitted from special elections, then Martha Coakley would be a US senator and Dean Tran would not be a state senator,” he added, referring to the recently elected Republican lawmaker from Fitchburg, who prevailed in a special election against a Democrat who had the backing of “the entire Democratic establishment.”