For nearly two decades, The Rothenberg Political Report didn’t break down Senate races into nine detailed ratings categories 22 months out from the next election. That was an era when there was something called an “off-year” — and those days are gone.  

For example, former Rep. Joe Sestak, D-Pa., began his challenge to GOP Sen. Patrick J. Toomey nearly two years ago. And some strategists argue Sestak never stopped running after he lost a close race to Toomey in 2010. Toomey is one of seven incumbent Republicans seeking re-election in states President Barack Obama carried in two presidential elections. The Pennsylvania Republican, Mark S. Kirk of Illinois, Ron Johnson of Wisconsin, Marco Rubio of Florida, Kelly Ayotte of New Hampshire and Rob Portman of Ohio start the 2016 cycle with competitive races in new ratings by The Rothenberg & Gonzales Political Report /Roll Call.  

Republican Sen. Richard M. Burr’s re-election race in North Carolina, where Obama won in 2008 but not 2012, is rated as Leans Republican, along with contests for Ayotte and Portman. Initially, the Pennsylvania and Florida races are rated as Tossup/Tilts Republican. Kirk and Johnson are the only two incumbents in the country who start with pure Tossup contests.  

Overall, Republicans are defending 24 seats compared to just 10 seats for Democrats, which is a reversal of the political landscape from last cycle .  

Democratic vulnerabilities appear to be limited to just two states. Former Democratic Senatorial Campaign Committee Chairman Michael Bennet’s re-election in Colorado is rated as Leans Democratic. His home-state colleague, Democrat Mark Udall, was defeated in November. And Senate Minority Leader Harry Reid can expect a tough race in Nevada if he seeks re-election. His race is also rated Leans Democratic, as Republicans search for a challenger.  

On one hand, it might be easy to rationalize difficult ratings by pointing out how much time there is before the elections. But since many contests are decided on fundamentals of the state and incumbency, the crop of competitive races does not generally change dramatically, at least in recent cycles.  

Four of the nine seats Democrats lost in 2014 were listed as Tossups nearly two years before the election . In January 2013, Alaska, Montana and North Carolina were rated as Leans Democratic, and Democrats lost the trio last November.  

Iowa was the one race Democrats lost that was listed as safe for them in the off-year. But that was because Sen. Tom Harkin decided not to seek re-election. Retirements can fundamentally change a race and pull a state onto the competitive playing field.  

That’s why GOP strategists will spend the first months of this cycle trying to avoid retirements. If Arizona Sen. John McCain and Iowa Sen. Charles E. Grassley opt for retirement, it will likely vault their seats into a Tossup status. If they seek re-election, Democrats probably won’t mount much of a challenge. (That being said, Democratic Sen. Barbara Boxer’s retirement does not change the initial partisan outlook of the California Senate race).  

In 2012, three of the four seats that changed party hands were listed as competitive in January 2011 . The one exception was Indiana, where Sen. Richard G. Lugar lost in the GOP primary, and nominee Richard Mourdock’s missteps during a debate doomed his chances. But even in the case of the Hoosier State, we wrote in February 2011 about Lugar’s vulnerability against a single challenger in the GOP contest.  

One of the most important things to watch this cycle is how Rubio and Kentucky Sen. Rand Paul balance presidential ambition with their re-election races, and what happens if Ayotte or Portman are chosen to be the running mate with the GOP presidential nominee, in the middle of a competitive re-election contest. It could be a case of what’s good for the presidential ticket might hinder Republicans’ ability to hold a Senate seat.  

Democrats need a net gain of five seats in 2016 to ensure a majority. They can control the Senate with a net gain of four seats if they hold the White House and a Democratic vice president becomes the tiebreaker.  

Related:

Pennsylvania Democrats Hesitate on Sestak Senate Bid


Script Will Be Flipped in 2016 Senate Majority Battle


The Rothenberg & Gonzales Political Report: 2016 Senate Overview ($)


Roll Call Results Map: Results and District Profiles for Every Seat


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