While the party that controls the White House "almost invariably" loses seats in the midterm elections, Democrats face the biggest headwinds going into the midterm season if they expect to take over one or both houses of Congress, according to Andy Friedman of The Washington Update.
In his recently released white paper, "The 2018 Midterm Elections: Context and Cross Currents," Friedman opines that in the Senate, Democrats' headwinds arise from the disproportionate number of Democratic senators running for re-election, while in the House the challenge comes from the effects of gerrymandering.
"The headwinds suggest that it will not be sufficient for Democrats to win the popular vote by a modest amount; a greater margin of victory will be required," Friedman states.
In the upcoming midterm, the Democrats need to pick up a net two seats to take control of the Senate.
As it stands now, Friedman says, the Republicans hold a 51-49 seat majority in the Senate.
A Democratic pickup of two seats would flip the 51-49 majority. (A Democratic pick-up of one seat would result in a 50-50 Senate, with Vice President Mike Pence breaking ties.)
"A two-seat gain seems eminently possible given the tendency of the party out of power to gain seats," Friedman states.
That being said, the 2018 election "is unusual given the party makeup of the candidates running for re-election," Friedman writes.
Incumbent senators running this year were last voted into office in 2012, he continues, in confluence with President Obama's victory that year.
"Many of those senators are running from states that now lean Republican," Friedman says, with 35 senators, of which 26 are Democrats, up for election this year.
Of those 26, 10 hail from states that voted for President Donald Trump in 2016 (Florida, Indiana, Michigan, Missouri, Montana, North Dakota, Ohio, Pennsylvania, West Virginia and Wisconsin).
Conversely, Friedman says, Democrats have a chance of picking up Republican seats in Arizona, Nevada, Tennessee and perhaps even Texas.
The "Senate math" basically comes down to this: To take the Senate, Democrats must win two seats currently held by Republicans as well as the 10 states that voted for Trump and the additional 16 states where they are incumbents (or pick up enough additional Republican-held seats to make up any difference), according to Friedman.
"That is not impossible, but it's much harder than saying the Democrats merely need to pick up two seats to produce a majority," he states.