No one expected Maine’s U.S. Senate race to be scintillating, but this one has fallen well below expectations. The last time there was an open Senate seat, in 1994, Reps. Olympia Snowe and Tom Andrews went at each other hammer and tongs, but the fight was clean and above-board.

Andrews later confessed, tongue in cheek, that he had picked “the perfect year to run as a liberal Democrat” – this was the start of the exceedingly short-lived “Gingrich revolution” – but at least the voters had a clear choice.

Compare that to the murky mess produced by the attack ads the Republican Party and the shadowy “Super PACs” have inflicted on us.

King, the front-runner, has been the target of most ads, which initially criticized his handling of state government – difficult to sustain, since King is widely seen as Maine’s most successful governor since at least Ken Curtis, long ago. The latest focus is those horrible wind towers King help install on Record Hill in Roxbury.

Strong majorities of voters support windpower, and they probably understand that to build wind turbines you also have to build access roads and pads for the towers. Whether they are really susceptible to ads where people pretend that the former governor was raping and pillaging his way across the countryside is doubtful, but that isn’t stopping the onslaught.

In truth, King has seemed a little rusty as a candidate this time out. He’s now 68, has been out of office for a decade, and his primary motivation seems to have been to go to Washington and strike a blow against mindless partisanship. It’s appealing, but it’s not really the basis for an effective campaign.

Explaining how Maine can turn its moribund economy around, what plans King has to improve health care, and what his stance is on public education are probably more what voters are looking for. But would those messages even get through amid the din?

The trouble with the GOP and Super PAC campaign so far is that they have been bombarding King without really doing anything for their preferred candidate, Charlie Summers.

If King has been a bit lackluster, Summers has been barely visible. You can attack and attack, but unless your candidate has something to say, it’s simply going to alienate voters.

The Republicans have noticed, though, that one of the beneficiaries of the attacks could be Democrat Cynthia Dill, by far the least well-known among the candidates. She has doubled her support since the June primary. Although admittedly coming from extremely low levels – 7 percent, in one survey — the voters the GOP is trying to peel away from Angus King aren’t headed in Charlie Summers’ direction. His support hasn’t moved over the one-third threshold, and that won’t get it done.

So the next gambit – attack Dill. The latest mailing from the Maine Republican Party proclaims that Dill is “too liberal for Maine.” It ties her to President Obama, which seems dubious given Obama’s commanding lead here over Mitt Romney. We are supposed to be shocked that Dill said, “I don’t think that being a progressive Democrat means that you’re partisan.”

It also zeroes in on a headline used for her op-ed piece: “Cynthia Dill: U.S. Senate campaign is a challenge against fear.”

I’ve long thought that Republicans are in danger of becoming the Party of Fear, but do they really think advocating fearfulness is going to win votes? Charlie Webster, the GOP chair, really must be losing his touch.

In the end, Angus King is probably going to be our next U.S. senator if this is the best the attackers can do. It may seem plausible that Dill, like Andrews before her, is “too liberal” to win a statewide race. But Dill’s real problem is that almost no one knew her when she won the primary, and in competing against a popular two-term governor she’ll have a tough time winning over even fellow Democrats.

The U.S. Supreme Court’s Citizen United decision allows, for now, wealthy individuals and corporations to spend unlimited money on elections, but advertising alone isn’t going to win races. A survey showing almost 40 percent of the viewers who still watch TV regularly zap out the ads seems to clinch that point.

Summers’ official website, should you want to check, also spends most of its space attacking King and Dill. It does say that Summers will “fight for jobs, fiscal sanity, and solutions to our looming energy crisis.” A few details would have been nice.