Pity the poor American voter.

As if listening to all the mudslinging and the whining, the backpedaling and the obfuscating weren’t bad enough, the electorate’s eardrums are also under assault from that most grating of noises: the candidate trying to sing.

And sing. And sing.

It’s President Obama’s fault. Well, Mitt Romney’s, too. Each shares some of the blame, although for different reasons. Romney because he insists on singing for audiences even though he sings really, really badly. Obama because he’s paying for campaign ads that force voters to listen to Romney singing really, really badly.

The sing-songy campaign theme has been all the rage this week because of dueling musical campaign commercials. An Obama ad slams Romney for his offshore investment accounts and accuses him of outsourcing American jobs while the former Massachusetts governor can be heard squawking and squeaking through “America the Beautiful.” The Republican candidate’s campaign hit back with an ad released Monday accusing Obama of enriching his campaign contributors and, in keeping with the theme, featuring the president singing Al Green’s “Let’s Stay Together.”

Really now, how could they do this to us? What have we done to deserve this?

Well, it turns out the answer is simple: Politicians think that serenading us will make us like them. And politicians like to do things that they think will make us like them. They’ve been doing it for decades, both marvelously and awfully, from former Louisiana governor Jimmie Davis’s irresistibly catchy rendition of “You Are My Sunshine” or President Harry S. Truman’s deft piano playing to Colin Powell’s butchering of “Call Me Maybe” and “YMCA.”

“It is a way to introduce yourself in a somewhat self-deprecating way,” former U.S. senator and Democratic presidential candidate Bob Graham said in an interview Monday.

Graham, who acknowledges he’s “no Pavarotti,” sang so much on the campaign trail that his handlers felt compelled to release a CD of his greatest hits. On the phone Monday, the longtime Florida politician half sang, half recited the lyrics of his favorite number: “Bob Graham is a cracker/ Be a Graham—cracker backer.”

Graham, like everyone in politics, has checked out the Obama ad lampooning Romney, but he’s also had the, ahem, pleasure of hearing Romney sing live. In person! And, even though he and Romney hail from opposite sides of the partisan divide, Graham can empathize with the Republican. “I think it’s a way in which he shows some of his humanity to his audience,” Graham observed.

And that’s really what candidates want to do. They want to show that they’re more than their policy proposals.

“Whether you can carry a tune or not, it conveys to average people that this is a person who knows how to have a little fun and is comfortable in their own skin,” said Mo Elleithee, a senior spokesman for Hillary Clinton’s 2008 presidential campaign who has also been a key adviser to former Virginia governors Tim Kaine and Mark Warner, as well as D.C. Mayor Vincent C. Gray.

That doesn’t mean, though, that campaign pros don’t sometimes “cringe” when candidates reach for the mike. The risk is that you “can appear to be a buffoon,” Graham said.

“There are times when it can be torture,” Elleithee said.

The torture can be self-inflicted by the candidate who just can’t help himself. But, even a more restrained candidate is at risk. For instance, a candidate who doesn’t sing along with patriotic songs would risk being labeled, well, unpatriotic. But should there be an open mike in the vicinity, that candidate could unknowingly — and forever — be providing the Internet with evidence of his tonal deficiencies.

Only the hardest of hearts couldn’t feel a bit sorry for Romney now that his croaky “America the Beautiful” is national news, just as some sympathies might have gone out to poor Hillary Rodham Clinton when one of those pesky mikes preserved her tone-deaf attempt at the Star-Spangled Banner during an Iowa stop in her 2008 presidential campaign. “Everyone sort of winced,” Elleithee recalled. “But it was okay. She was just being real.”

Thankfully, Elleithee said, Warner — now a U.S. senator — tended to limit his singing to the safe confines of a campaign vehicle. “That wasn’t something I’d necessarily want to subject someone to,” Elleithee said. “If he gets out of politics, I don’t think music is going to be a fallback career.”

But other times, Elleithee has found himself knocked over by the musical chops of his clients, like the time he heard a “ridiculously hot harmonica riff” coming out of a studio where he’d stashed Kaine to cut some radio spots. Since then, Kaine seems to be blowing into his harmonica every chance he can get.

Perhaps Kaine can offer to accompany Romney sometime in a gesture of bipartisanship during this most partisan of seasons. The biggest favor might be to simply drown him out.

“I think Mr. Romney sounds a little stressed,” Susan Derry, a professional singing coach based in Rockville, said Monday after listening to Romney singing on the Obama ad. “He has pitch issues. It sounds strangled.”