In the 2011 cycle, conventional wisdom suggested that Republicans would gain control of the Senate, mainly because of opportunities in Wisconsin, North Dakota, Montana, Nebraska, Missouri and Virginia. However, indications are suggesting that Republicans have a 50% chance of actually losing seats. Democrats have surged in states such as Virginia and Massachusetts where Nate Silver has given the Democrats a greater than 80% chance of winning. Also, Missouri and Indiana originally resembled Republican wins but the Republican candidates Todd Akin (R) and Richard Mourdock (R) hurt their chances with offensive comments about rape. Republicans still hope they can gain seats in the high prairies in NE, MT and ND. Although they have a shot in NE, MT and ND are both close races where likeable Democrats face not so likeable Republicans in states where personality is important. Anyway, here are my ratings. By the way, I have removed the tossup column because I believe by now, Senate seats should shift one way or the other (even though in a few states, specifically AZ, MT, NV, and ND, it was particularly difficult to make a decision.)
On another note, I am not including writeups on most Safe and Likely seats, they can be found here though: http://racesandredistricting.blogspot.com/2012/09/senate-rankings-september-2012.html
Blue =Likely Democratic
Light Blue = Lean Democratic
Very Light Blue=Tilt Democratic
Light Red=Tilt Republican
Dark Red/Brown=Safe Republican
Dark Green = Safe Independent
Green =Likely Independent
Gray= no election
Projected Senate turnover: Democrats +2
Republicans gain two: NE, ND
Democrats gain four: IN, MA, ME, NV
Safe Democratic (10 seats) CA, DE, MD, MI, MN, NJ, NY, RI, WA, WV
Likely Democratic (5 seats) FL, HI, NM, OH, PA
Lean Democratic (4 seats) CT, MA, MO, VA
Tilt Democratic (4 seats) IN, MT, NV, WI
Tilt Republican (2 seats) AZ, ND
Lean Republican (1 seat) NE
Likely Republican (0 seats)
Safe Republican (5 seats) MS, TN, TX, UT, WY
Safe Independent (1 seat) VT
Likely Independent (1 seat) ME
Seat changes favoring Democrats
NE Likely R-Lean R
Seat changes favoring Republicans:
AZ Tossup-Tilt R
WI Lean D-Tilt D
Overall, how do Republicans gain a path to a Senate majority? Well, they already have 47 seats and need 4 seats to win a majority, assuming Obama wins reelection and Biden is the tiebreaker. Nebraska is already Lean R and Maine is Likely Independent (Angus King probably will caucus with the Democrats,) so Republicans need to sweep all tilt R and tilt D which includes retaining AZ, IN and NV and picking up WI, ND and MT. That still only gives them +3 so they must win one of the leaning Democratic seats, CT, MA, MO or VA. Democrats have leads in all those states so it makes it difficult for Republicans to make a surprise win and I am 100% certain Republicans cannot sweep all the tilt D and tilt R states. Overall, Republicans have a very difficult path to the Senate majority.
Anyway, here is a more in depth look at the Lean and Tilt seats.
Lean Democratic (4 seats)
Connecticut (Open-Joe Lieberman): Rep. Chris Murphy (D) is facing Linda McMahon (R), former WWE CEO who spent around $50 million in the 2010 Senate race (she lost by 11 points) but is running closer in the polls than in 2010. In late August, McMahon was tied in the polls after she sent an ad blitz into Connecticut. Murphy though was boosted after the DSCC spent money to help him. Although September showed a close race, the newer polls are showing around +5 for Murphy, suggesting a similarity with the 2010 race where McMahon ran a close race in September but lost points close to the election.
Massachusetts (Scott Brown (R)): Brown seemed to be invincible after winning Ted Kennedy's (D) former Senate seat in this heavily Democratic state in a 2010 Special Election until Elizabeth Warren (D), Obama's nominee for the Consumer Protection Bureau decided to run. Warren has been a prolific fundraiser and is one of the top 15 highest fundraisers in Senate history. She also raised $12.4 million in the 3rd Quarter (compared to 7.45 million for Brown) and has performed well in the debates. Brown said his role model was Scalia which plays into Warren's strategy that a vote for Brown is a vote for a Republican to control the Senate. This is Warren's strategy because polls including a PPP one released on October 11th shows that 53%-36% of Massachusetts residents want Democrats to control the Senate. Brown has been running away from the Republican party but Warren has been tying him to the unpopular Republican Congress. Also, Brown probably feels sad he did not accept Super PAC money because Warren is outraising and outspending him. Brown also skipped the last debate. Also, Brown has led in only one poll since mid September. Warren should win this seat.
Missouri (Claire McCaskill (D)): I was at first very worried about McCaskill's chances here because of Missouri's sharp turn to the right (it was the only swing state in 2008 to support John McCain and it voted Republican for Senate by 13 points in 2010.) Then Republican candidate Todd Akin (R) said his famous legitimate rape comment which turned a 5 point Akin lead into a 5 point McCaskill lead. The NRSC and other Republican groups have come back and spent money here but McCaskill still has a strong advantage here.
Virginia (Open Jim Webb (D)): This race pits two former Governors against each other, Tim Kaine (D) and George Allen (R). For Kaine to win, he has to perform well in Northern Virginia, winning with 60%+ in Fairfax County and carrying bellwether Loudon County. Also, high African American turnout in the Hampton Roads/Richmond area should help Kaine too. Kaine and Allen are both well known so most voters have chosen a side so the candidates have to focus on turning out their voters. Recently though, Kaine has opened a lead with even Rasmussen showing him leading Allen. I considered placing this seat in Tilt Democratic but after the favorable polling data for Kaine, I am planning on moving it into "Lean Democratic."
Tilt Democratic (4 seats)
Indiana (Open Richard Lugar (R)): The Republican Legislature gave Rep. Joe Donnelly (D) a Republican leaning seat after redistricting which urged Donnelly to run for Senate. Mourdock defeated 36 year incumbent Lugar in a primary by claiming Lugar was not conservative enough for Indiana (Democrats may win though because Mourdock may be too conservative for Indiana.) To win, Donnelly needs to convince the voters that is the case. He also needs to perform well in not only Indianapolis and the Chicago suburbs but also win a big margin out of St. Joseph County (South Bend,) which is in his district and hit 40%+ in heavily Republican Elkhart County which is also in his district. Polls show many undecided voters are Lugar backers in the Republican primary so Donnelly has been tying himself to Lugar, including mentioning how Lugar and him both backed the auto bailout which saved Indiana jobs. At first, I expected those disaffected Lugar voters to move to Mourdock in the end but after Mourdock's rape comments, a Howey-DePauw poll (they are very reputable in Indiana,) showed Donnelly with an 11 point lead. I expect Donnelly to now win here.
Montana (Jon Tester (D)): Rep. Danny Rehberg (R) is challenging Tester, a popular incumbent with strong campaign skills (who can forget his haircut ad: http://www.youtube.com/watch?v=joQi27QG7Cs) Rehberg however is well known and popular throughout this Republican leaning state, making it more difficult. Like in 2006, this race could be one of the last Senatorial races decided and the polls reflect a very tight race. What Tester has to do is to win over some Romney voters who are conservative on guns while capitalizing on Obama turnout in the cities. In 2006, Tester won by carrying Native Americans and urban voters. He needs to replicate this to win. Also, Tester should keep margins down in the rural areas by talking about his authenticity as a regular Montanan while portraying Rehberg as a false Montanan. This race should be a nailbiter but I am giving the edge to Tester because even Rasmussen showed a 1 point lead for him and Rehberg seems to be a poor fit for Montana voters.
Nevada (Dean Heller (R)): This is another chance for a Democratic pickup as Rep. Shelley Berkley (D) from Las Vegas challenges appointed Senator Heller, a former Representative from the northern part of the state. Recently Berkley is making a wise campaign move by campaigning heavily in Reno because voters there are unfamiliar with her. She does not want to repeat the 2006 gubernatorial race where Dina Titus (D), a Las Vegas centric candidate over performed in Vegas but lost because she underperformed in Reno. Heavy turnout in Las Vegas should help Berkley (early voting in Clark County so far is 47% Dem and 33% Rep,) but unless she can win Clark County by more than 10 points, she needs to make inroads in Heller's base. Also, Nevada is underpolled in the Democrats favor. There are two reasons for this, the first one is that most polls do not have a Spanish speaking option (and the ones that do such as Mellman which was the only polling firm to predict Reid's 2010 win showed Berkley up 3,) and the 2nd is Nevada's Democratic Party's organization strength. The underpolling made a big difference in 2008 when polls showed Obama leading by 6 but he ended up winning by 12 in Nevada. Also, the Harry Reid organization is working strong for Berkley. This was a tough decision for me but I decided to rank Nevada at Tilt Democratic because of the Democratic organization but I expect a very close race here.
Wisconsin (Open Herb Kohl (D)): Rep. Tammy Baldwin (D) from Madison is running for the seat against former Gov. Tommy Thompson (R). At first, Republicans thought that this seat would be an easy pickup for them because Thompson is moderate and won reelection with 60%+ as Governor. Conventional wisdom also said Baldwin was too liberal for the state. What conventional wisdom did not say though was that Baldwin would campaign extremely hard throughout August and September while Thompson made only a few campaign appearances due to his "frail health." Baldwin gained a lead in September and was helped when Thompson's son said, "Obama should go back to Kenya," which should hurt the Thompson campaign. However, Thompson has been bouncing back, even leading in a few recent polls although Baldwin still has a slight advantage.
Tilt Republican (2 seats)
Arizona (Open Jon Kyl (R)): Democrats have a strong candidate, former Surgeon General Richard Carmona (D). He served under George W. Bush and was a registered Independent until recently. He also is campaigning as an Independent frustrated with gridlock and has criticized the Bush Administration which is helping him with Independents. The Republican candidate is Rep. Jeff Flake (R)-Mesa who was leading early this year but polls show a narrowing race. In early October, a few polls showed Carmona leading. No polls were released last week though and the last poll released was a Rasmussen one showing Flake ahead by 6. I am extremely unsure about whether to rank this race Tilt Republican or Tilt Democratic but I decided on Tilt Republican because of how although Hispanics are underpolled here like in Nevada, Arizona lacks the strong Democratic organization of Nevada. This was a tough decision for me and I believe Flake has a <60% chance of winning here.
North Dakota (Open Kent Conrad (D)): This race resembles the Montana race. It is a primarily rural and Republican leaning state with a moderate likeable Democrat facing a not so popular Republican U.S House member. Many North Dakotans vote for the person, not the party and Berg is not very personally popular which works in Heitkamp's favor. She is very likeable and a news reporter described her as "the person who hugs everyone in the room while Berg is the person in the room who gives talking points about why you should vote for him." North Dakota really likes personally popular candidates (Kent Conrad won easily because he is personally popular,) but it is a Presidential year and North Dakota should go for Romney. Berg's new theme though is "you may like Heidi but she likes Obama." I personally believe this race is very close but I will give the edge to Berg for now, noting how the undecideds are Republican leaning voters. Heitkamp still has a strong chance and I expect this race to be 1 point either way.
Lean Republican (1 seat)
Nebraska (Open Ben Nelson (D)): Conservative Democrat Ben Nelson has retired and Democrats found former Sen. Bob Kerrey (D), their best candidate to retake this seat. Republicans picked Deb Fischer (R). Kerrey was once very popular in Nebraska but since his Senate retirement, Kerrey has been President of Eugene Lang College in New York City, hurting his Nebraska roots. Kerrey received a recent boost from comedian Steve Martin who endorsed Kerrey and released a strong ad for him here http://www.huffingtonpost.com/2012/10/05/steve-martin-bob-kerrey_n_1942521.html (Martin also has not endorsed candidates until now.) Former Sen. Chuck Hagel (R) endorsed Kerrey too and this momentum has narrowed the race. An Omaha World Herald poll on October 25th showed Fischer with a 3 point lead, down from a 16 point lead in September. Kerrey has narrowed the race but I think it is too late to win (although a win would be a very pleasant surprise.)