We're up to our 7th midterm election update & there are big changes again this week. Here's what history tells us about midterm elections:
Since the advent of the current two-party system (39 midterm elections) we've averaged the President's party losing 4 Senate seats and 30 seats in the House. If that happens this year Democrats would retake control of both chambers of Congress. Democrats only need to flip two Senate seats to retake control and they need 24 seats in the House. History is on the side of the Democrats reclaiming control going into this cycle.
There are only three times that the incumbent President's party has gained seats (1934 during FDR's first term, 1998 during Bill Clinton's second term and 2002 during George W. Bush's first term) thus only 3 out of 39 midterm elections have resulted in the President's party gaining seats. Here's another way of looking at it... History suggests there's a 92% chance Democrats will gain Congressional seats this year. The question becomes how many. That's where it's helpful to look at the history of generic ballot polls and outcomes. These are the past four cycles:
The first number is the average generic ballot polling on Election Day and the second is the actual result:
2014: GOP +2.4 - GOP +5.7 = GOP+3.3%
2010: GOP +9.4 - GOP +6.8 = GOP -2.6%
2006: DEM +11.5 - DEM +7.9 = DEM -3.6%
2002: GOP +1.7 - GOP +4.6 = GOP +2.9%
The first takeaway is that the polls average being off by about 3%. There's no rhyme or reason politically (polls were overly representative of both parties twice). So next let's try to see what cycle this one most resembles. As of today, the generic ballot says...
Current: DEM: +8.8%
This week resulted in another shift in favor of Democrats. On back of the shooting and public sentiment that favors action in the wake of it - Democrats gained an additional 2.3% advantage on the generic ballot. That's a significant move because at this stage of the process - it potentially would be the difference between Democrats being able to completely regain control of Congress rather than just flipping one chamber. This margin isn't quite wave territory but it's close.
Last week Democrats were on pace to add 15 seats in the House and 5 in the Senate. This week Democrats are positioned to gain 29 seats in the House and 5 seats in the Senate.
In the House there was a major development independent of public sentiment that moved in favor of the Democrats as well. There are at least three additional seats in Pennsylvania that are likely to flip with the recently redrawn state map. If this map holds through any additional changes that might occur it might be the difference in the control of the House in November.
The major caveat is that the Senate map is highly unfavorable for Democrats this year. We'll need to wait until we're past the primaries and can track individual races to have a clearer picture of what the playing field looks like...but if this margin were to hold by November I do currently show Democrats being able to win at least two additional seats regardless. Under this week's update Democrats would likely regain complete control of Congress if the elections were held today.