In 2012, 23 Democratic Senate seats were available, as opposed to 10 Republican seats. An increase of four seats would have given the GOP a Senate majority. In the election, three GOP seats and one Democratic seat was lost, increasing the Democratic majority by two.
DSCC executive director said their strategy was to “localize” elections – make them “a choice between the two people on the ballot...and not simply allow it to be a nationalized election”. Because this is not easy to do in a presidential election year, the DSCC has gone very much on the offensive, depicting Republican candidates and donors, and especially the Tea Party, as extreme. During the Florida and Indiana primaries, they are pushing that the Tea Party is working to move the GOP "so far to the right that candidates will say anything to get their party's nomination". The GOP is targeting four red states to pick up the seats they need for a Senate majority. They were looking at states that didn't swing for President Obama in 2008: Missouri, Montana, Nebraska and North Dakota.