The Fix is moving the Massachusetts Senate race from the “tossup” category to the “lean Democratic” column, a reflection of Elizabeth Warren’s momentum in the contest.

Warren has opened up a slight and consistent lead over Sen. Scott Brown (R), recent polling shows. The Real Clear Politics average of Bay State polling shows Warren leading Brown by almost five points after the two candidates were running about even for much of the summer.


As the map above shows, if Republicans don’t hold Massachusetts, the prospect of seizing back the Senate majority looks decidedly daunting. The GOP would need to win all six tossup races just to gain a 50-50 tie in the Senate (assuming every state that is currently red or blue on our map stays that way). If President Obama wins reelection, 50-50 means Democrats would still control the upper chamber.  (On the map, yellow states are “tossup” races, the light blue and red ones are “lean” Democratic and Republican contests, and the dark blue and red states are “solid” Democratic and Republican races.)

Back in Massachusetts, Brown and Warren have debated three times and the Democrat has appeared to grow stronger with each outing. She’s effectively batted back attacks – both in the debates and over the airwaves – against her claim to Native American heritage, and she's been linking Brown to the national GOP with more frequency. Through it all, Warren has set a remarkable fundraising pace.

A big key to Brown’s political success is his image. He’s run multiple ads portraying himself as an every-man. His pickup truck, which was a staple of his 2010 special election victory, is back on display once again. Brown's wife has even vouched for his credentials as a father and husband in commercials. And the senator regularly underscores his local roots on the campaign trail. 

But the latest WBUR survey (which shows Warren holding a slight lead) reveals that Brown’s favorability edge has disappeared. His fav/unfav split (49/38) is about the same as Warren’s (49/39) in the survey, whereas in the previous poll, the Republican's split (54/41) looked better than the Democrat’s (47/38).

Brown has maintained a significant advantage among independents throughout the campaign – the WBUR poll shows him winning voters who aren’t Democrats or Republicans by a whopping 22 points – but he is still losing. That speaks to just how heavily Democratic the state of Massachusetts is and how daunting the math is for Brown.

The race isn’t beyond Brown’s reach just yet. He will debate Warren a final time next week. A strong showing could move the needle in his favor. And Brown has run a competent campaign and excels on the stump.

But 2012 isn't 2010. He’s run up against superior competition and a less favorable macro-environment. Those factors could be enough to send him packing.