(CNN) – The battle for U.S. Senate in Massachusetts, which seemed over the summer to be the nation's most civil political race, has morphed into one of the ugliest.
In just the last three days, dueling attack ads have reignited the debate over Elizabeth Warren's Native American heritage, with Sen. Scott Brown, Warren's Republican rival, suggesting in his spot that Warren is untrustworthy.
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Warren fired back, producing an ad claiming Brown was attacking her family.
On Tuesday, videotape surfaced of Brown staffers making offensive gestures at a Warren rally that seemed to mock Native Americans. The principal chief of the Cherokee Nation called the "war whoops" and "tomahawk chops" "offensive and downright racist," saying the actions "perpetuate negative stereotypes and continue to minimize and degrade all native peoples."
Asked about the tape Tuesday at a press availability at Boston's South Station, Brown said he hadn't seen the footage but did not support the actions as described by reporters.
"That's not something I condone. It's certainly something that if I am aware of it, I'll tell that member to never do it again," Brown said, before launching into an attack on Warren's claims to Native American heritage.
It's all a sudden move to the low road for two candidates who seemed determined earlier in the race to stick to the issues. Both signed a pledge in January calling for super PACs and other third party groups to stay out of their contest, hoping to keep focused on issues that affect the Bay State. The campaigns also promised not to coordinate with any groups planning to launch "sham ads" during the course of the campaign.
READ MORE: Elizabeth Warren vs. Scott Brown: Priciest race this year
Brown stuck largely to a message of bipartisanship on the stump and in interviews, keenly aware of Massachusetts' moderate Republican base he hopes to win in November.
In an election year when most Republicans running for re-election boast about their votes blocking President Barack Obama's agenda, Brown has bragged about helping the Democratic incumbent.
"I can name a litany of Democratic-sponsored bills that never would have passed had it not been for me," Brown told CNN in July. "The president had called me. The vice president calls me. Secretary [of State Hillary] Clinton calls me for my vote all the time."
That claim was followed up with a fact-check in the Boston Globe, which reported Clinton and Brown had spoken twice by phone. He spoke with Biden and Obama each once by phone, but has held in-person meetings more frequently with the president and vice president.
At the beginning of September, Brown produced an ad showing him shaking hands with Obama.
"Good job," the president is seen saying in the spot.
Warren, for her part, focused largely on her record as a consumer advocate, rather than on Brown, using her speeches to tout her record as the brains behind the new Bureau of Consumer Protection.
At the Democratic National Convention, Warren delivered a strident speech that brought a packed convention arena to its feet in thunderous appreciation – but didn't mention her rival by name.
"Americans are fighters. We are tough, resourceful and creative. If we have the chance to fight on a level playing field – where everyone pays a fair share and everyone has a real shot – then no one can stop us," Warren said.
Until Warren's prime-time address at the DNC, the race remained close. But a pair of surveys after the speech showed the Democratic candidate pulling ahead of Brown, 48%-44% in a Suffolk University/7News poll and 50%-44% in a Western New England University poll.
And thus the onslaught began, with Brown launching full tilt into an attack on Warren's claims to Native American ancestry.
READ MORE: Elizabeth Warren: Is she or isn't she Native American?
Last week, Brown opened an hour-long debate with the issue, claiming Warren wasn't being totally transparent about why she was listed at Native American when she was a professor at Harvard Law School.
"Professor Warren claimed that she was a Native American, a person of color and as you can see, she's not," Brown said. He repeated his call for his opponent to release records showing whether she had claimed Native American heritage on job applications.
"When you are a U.S. Senator, you have to pass a test and that's one of character and honesty and truthfulness. I believe and others believe she's failed that test," Brown said.
That attack was followed by the television spot, which Warren rebutted with a spot of her own.
"Let me be clear. I never asked for or never got any benefit because of my heritage," she says, addressing Brown's central concern. "The people who hired me have all said they didn't even know about it."
"Scott Brown can continue attacking my family, but I'm going to keep fighting for yours," the former Obama administration official concludes.
On Wednesday, Brown made another attempt at cracking Warren's image as a crusader for the middle class, addressing a letter to his rival asking her to disclose her outside legal work while she was working as a professor at Harvard Law School.
Brown cites reports that Warren provided legal counsel to Travelers Insurance and LTV Steel while she was a professor, which Brown claims in his letter "is at odds with the image you portray on the campaign trail fighting for the middle class and the little guy."
"During this campaign, you have accused others of siding with big corporations," the GOP senator concludes. "As it turns out, you are the only candidate in this race who has stood on the side of large corporate interests over the middle class."
At a press conference in Boston Wednesday, Warren countered Brown's claims by pointing out her rival has "never released the name of a single client," according to the Boston Herald.
"I think what he's trying very hard to do is not talk about his voting record. So let's keep count, so far he's come after my family, he's come after my teaching, he's come after when I've gone to the U.S. Supreme Court," she said.
CNN's Ashley Killough, Dana Bash and Alison Harding contributed to this report.
Sen. Brown's staffers have cost him this election. Scottie should have just stuck to this issues rather than demonize Ms. Warren's heritage. Oh wait I forgot. He's Wall Streets favorite senator and he can't run on the issues. He better go back to soliciting his daughters.
"As it turns out, you are the only candidate in this race who has stood on the side of large corporate interests over the middle class."
Four words for you Sen. Brown: CONSUMER FINANCIAL PROTECTION BUREAU
Wow. Gotta love the false equivalence here. Someone does something disgusting ("war whoops" etc) and then someone condemns and criticizes it for being disgusting and CNN jumps right in to condemn the second person and group them in with the first person as "negative." Go take a leap, CNN.
Brown pulled the race card. He's done.
Yes, just what the US Senate needs, another far left loon from the Fidel Castro wing of the Democrat Party. It is just hilarious to hear this rich Harvard elitest spew about things being rigged against people and about leveling the playing field. What she is really talking about is socialism and endless attacks on the companies that provide millions of jobs in this country. If you REALLY want to have record unemployment and debt, elect Warren. She'll guarantee that and then some. Of course then blame it on others, as the lefties always do. Their faulty inferior ideas are never the problem it seems.
Old Pocahontas is a Communist!
presidents now rule by decree, congress has become irreverent, only coming out of their cash grabbing stupors to rubber stamp, or pointlessly nag.
rs - Brown pulled the race card. He's done.
Actually Warren pulled it decades ago when she claimed to be part Indian. I guess she wasn't happy being a rich Harvard elitest or maybe felt guilty and wanted to be able to identify with the unwashed masses? Either way, she is a liar, like most leftists are. They always want to hide their true identity, just like Obama.
Are you kidding CNN? "In Massachusetts, Brown and Warren in ugly sprint to finish." What a crock, Brown is in the ugly race to the finish. Warren has not leveled a single attack not on his record, and even so she barely does attack ads. He is playing ridiculously ugly and yet you loop them together as both playing typical politics in order to seem fair. Pitiful.
I KNOW all the lefties in here will REALLY support Brown because he is in the military and has served his country. I know that concerns a lot of you because you've brought it up about others. Elizabeth Warren? She NEVER served in the military even though she could have. Scott Brown thanks you for your support!!
brown is one of the only senators who does a good job and is not so one side to his national party...
Scott Brown is less than a man. Whatever positives he had before, he surely has lost it. When he told viewers to look at Ms. Warren's feature in re her heritage, wow, how racist can you be. Through intermarriage and other factors one does not have to 'look' like a person of any particular race and color. Is this his burning issue? I thought from afar that he was a different type of Republican, but just like Romney he has done well to hide his 'dark side'. Go Warren, go! She is the one who dealing with the issues that people care about.
I really like it when people use the word "elitist" because it gives me a quick heads-up that they let talk radio morons do their thinking for them. Poor babies, can't even form their own thoughts and opinions.
truth hurts – Now, this is going to be very painful for you, because, you know, the truth hurts, but Liz Warren is going to win the race against the centerfold boy, and President Obama is going to beat that robot that talks through his nose. You like apples? How you like them apples? Sorry to disturb you, please resume your pajama party in your mom's basement.
Wait till the Brown/Jenzabar scandal rears it's ugly head. Brown and his family had luxury suites at Patriots games paid for by lobbyists. Just google brown jenzabar maginn and you'll get some of the stories.
Brown is just another MEAN Repub/teap!
Vote them all out!
Scott Brown, serves the rich and the workin' class, can oh well just go to, and I ain't talkin' heaven
Where r our native americans brothers and sisters? Why arent they out protesting n our streets! Discusting. Keep it up republicans keep making it about the white rich man. What fools!
"It is just hilarious to hear this rich Harvard elitist spew things..............."
Glad to know you have finally caught on to Romney, "another loon" from all wings of the Republican/Tea Party.
This article accuses them both of taking the "low road", but the only ugly things that have been done came from Brown's side of the fence. And Brown's staff mocking Native American's is absolutely inexcusable. It seems like a lot of the GOP candidates have been drinking their precious heavy metal saturated mine water.
Ask Sen. Scott Brown he will say money is not helping
If I were Scott Brown, I, too, would try to get voters to focus on a non-issue such as Elizabeth Warren's heritage. Otherwise they might ask themselves whether they want a senator who won't vote for tax cuts for 95 percent of Americans unless the richest 1-2 percent get their taxes cut yet again (even when they're rolling in money from previous tax cuts). Whether they want another Republican in the Senate to maintain 40 Republican votes to ensure that nothing gets done. Whether they want a senator who won't reduce the Pentagon's budget even though Republicans howl about the dangers of the deficit. Whether they want a senator who won't vote for stimulus spending to reduce unemployment but who thinks that more tax cuts will magically increase employment. Whether they want a senator like Brown who professes to care about the environment until it comes time for a vote. If people look closely, they will see that Brown is not that far from the Tea Party Republicans. Don't let the fact that this professional politician rides around in a pick-up truck fool you into thinking he's really for the little guy. Yeah, Warren's heritage sure is an important issue.
I do not know how anyone who had watched the video of Brown's senate staff making fun of Native Americans and Ms. Warren can vote for Brown.
The actions and words of Rick Brown and his staff are pure .........racism!
PS. Meant to write ......."Scott Brown"!
Brown voted against middle class jobs – this alone is reason enough to show this wall street lapdog to the door.