This year, Democrats have 23 seats up for reelection (including the two independents that caucus with them) while Republicans have only 10 seats up for reelection. According to the final HuffPost Pollster estimates, the combination of returning senators and candidates leading in the 2012 contests gives Democrats 50 seats and Republicans 45 seats. An independent candidate from Maine, who is expected to caucus with Democrats, continues to lead in the polls and there are four races rated as "toss-ups."
To win a majority, Republicans not only need to win those four "toss-up" races but also make at least one inroad into a race that currently "leans Democratic." Meanwhile, if Democrats win a majority of the "toss-up" races, they have an opportunity to expand their current majority
Last February, Sen. Jon Kyl (R-Ariz.) announced that he would not be seeking a fourth term in 2012. Rep. Jeff Flake (R-Ariz.), who emerged from a bruising, expensive Republican primary in August, will face Richard Carmona (D), a former surgeon general under President George W. Bush, in the general election. Flake and Carmona are deadlocked in the polls but many voters are still undecided, since the candidates were largely unknown to the broader Arizona electorate. Flake has faced criticism for his past.
Despite middling job approval ratings, Sen. Bill Nelson (D-Fla.) is in a relatively strong position to win reelection. His opponent, Rep. Connie Mack IV (R-Fla.), was initially seen as a weak candidate due to his lackluster fundraising, despite his family’s fame in the state. Though polls pointed a close race over the summer, Mack has fallen behind Nelson in most polls since then. Several pro-Republican groups, such as the Crossroads GPS have aired ads attacking Nelson in an attempt to shrink his lead. However, time is running out and Nelson’s lead may now be insurmountable.
Sen. Daniel Akaka (D-Hawaii) announced he was stepping down in 2012, creating a rare open seat opportunity in the Aloha State. Though Republicans landed a strong recruit in former Gov. Linda Lingle (R), she remains the underdog in the general election against Rep.Mazie Hirono (D-Hawaii), especially with native son President Barack Obama at the top of the ticket. However, Lingle narrowly defeated Hirono in the 2002 governor’s race and has raised more money than her opponent this year. This race has been sparsely polled so far, but Hirono has led by varying margins.
Sen. Olympia Snowe (R-Maine), one of the most moderate Republican senators, abruptly announced her retirement in February. Angus King, an independent former governor whoespecially on social issues. The DSCC
In the marquee Senate race of the cycle, Sen.Scott Brown (R-Mass.), who unexpectedly won Ted Kennedy’s old Senate seat in a 2010 special election, is facing a much stronger candidate this time in Elizabeth Warren (D), a Harvard Law professor and special advisor for the Consumer Financial Protection Bureau. Polls have consistently shown an extremely tight race, while President Obama has consistently led Mitt Romney by double digits, which speaks to Brown’s popularity in the state. Brown has largely been campaigning as an independent with bipartisan credentials, while Warren describes herself as a champion for the middle class, highlighting her efforts to make Wall Street and big banks more accountable to consumers.
Freshman Sen. Jon Tester (D-Mont.) is facing a tough challenge in 2012 from Rep. Denny Rehberg (R-Mont.), a top-tier Republican candidate who has represented the entire state since 2001.
When moderate Sen. Ben Nelson (D-Neb.) announced his retirement, Republicans saw it as a relatively easy opportunity to flip this seat in 2012. Democrats recruited former Sen. Bob Kerrey (D-Neb.) to run in Nelson's place. On the Republican side, state Sen. Deb Fischer (R) came from behind to defeat two better-known and better-financed opponents in the primary.
Amidst an ethics investigation, Sen. John Ensign (R-Nev.) who is being investigated by the House Ethics Committee for allegedly using the powers of her office to aid her husband’s medical practice. Expecting a close race, the NRSC and DSCC have been flooding the airwaves with ads on behalf of their party's candidate. Most polls have shown Heller with a narrow edge over Berkley, but if Berkley can drive up Latino turnout and pull off the upset it would all but ensure that Democrats maintain a majority in the Senate.
After Sen. Jeff Bingaman (D-N.M.) announced his retirement last February, Republicans were bullish on their chances to take over this seat. However, the Land of Enchantment has become much more Democratic over the last decade, and Rep. Martin Heinrich (D-N.M.), the Democratic nominee, has held a sturdy single-digit lead over former Rep. Heather Wilson (R-N.M.) in the polls. The NRSC tellingly Crossroads GPS and the airing a barrage of negative ads against Wilson. The shifting demographics of New Mexico may be too much for Wilson to overcome to pull off the upset.
When Sen. Kent Conrad (D-N.D.) announced his retirement last year, most political observers expected this race to be an easy pickup for Republicans. Freshman Rep. Rick Berg (R-N.D.) announced he was running for the open seat and started off as the strong favorite to replace Conrad. However, Democrats recruited former state Attorney General Heidi Heitkamp (D) to run, and she is giving Berg a run for his money. All indications point toward a tight race: Heitkamp has been running neck-and-neck with Berg in the few polls that have been conducted and the NRSC have run ads attacking Heitkamp for supporting Obamacare, while Heitkamp has been running to the center, especially on energy issues. Although Heitkamp has proven to be a strong candidate, she must still outperform President Obama by a significant margin to prevail in North Dakota.
Many Republican-aligned outside groups have turned their attention to Ohio, where they have spent millions of dollars on ads in an attempt to sully the image of first-term Sen. Sherrod Brown(D-Ohio). While some polls have found that Brown’s lead has shrunk since the ad barrage, his numbers have largely held up against his opponent, state Treasurer Josh Mandel (R), a 34-year-old Iraq war veteran and fundraising magnet with a un-American” for supporting it -- arguing that it hurt the pensions of non-union employees.
Republicans failed to recruit a top-tier candidate to run against freshman Sen. Bob Casey (D-Pa.) in 2012, despite his mediocre approval ratings. Former coal company executive Tom Smith (R) emerged from the April Republican primary.
After narrowly defeating incumbent George Allen(R-Va.) in 2006, Sen. Jim Webb (D-Va.) decided not to run for a second term in 2012, setting up a closely contested open seat race in an important swing state.
The retirement of four-term Sen. Herb Kohl (D-Wis.) turned a sure-fire Democratic hold into a possible pick-up opportunity for Republicans. Emboldened by Gov. Scott Walker’s (R) recall victory in June and Rep. Paul Ryan’s (R-Wis.) presence at the top of the ticket, the GOP thinks that Tommy Thompson (R), a former health and human services secretary and four-term governor, has a real shot to flip this seat. Most polls initially showed Thompson leading Rep. Tammy Baldwin (D-Wis.), who represents the liberal bastion of Madison, but the race is now almost dead-even heading into Election Day. Since the primary, Democratic groups have launched an ad blitz against Thompson over his past as a Washington lobbyist, claiming that he is beholden to special interests. Thompson, who survived a bruising, expensive Republican primary, spent that time refilling his campaign coffers and was largely off the airwaves. Baldwin, who has a liberal voting record, is expected to underperform Obama in Wisconsin, which would make the math very difficult for her if Mitt Romney carries or comes close to winning the state.