If elected, Hillary Clinton would make history as the first woman to occupy the Oval Office. There is, however, another historical precedent she might set. If Clinton wins the presidency, and the Republicans retain the Senate and the House of Representatives, it will be the first time in the history of the Democratic party—going back 188 years—that a Democrat will be elected president with the opposition party controlling both chambers of congress.
Only three times in the history of the office has a newly-elected president been faced with the opposition party controlling both houses—Zachary Taylor in 1848, Richard Nixon in 1968 and George H. W. Bush in 1988. Of those three, Zachary Taylor, as a Whig, predates the modern two parties. Three vice-presidents found themselves facing unified opposition after becoming president through the line of succession: Millard Fillmore after Taylor's death; Gerald Ford after Nixon's resignation; and Andrew Johnson, as a Democrat on a unity ticket, after Lincoln's assassination. But none were subsequently elected in their own right.
Granted, for all the reasons Doug Sosnik lists, Democrats have a good chance of retaking the Senate. But, even if Democrats only lose the House, Clinton would start her presidency with less freedom to operate than any other modern-day Democratic Party president. Since Grover Cleveland's second administration in 1892, every elected Democratic president has taken office with both houses of Congress—an unbroken run of 124 years.
The dubious distinction Clinton faces has a broader dynamic behind it—we are in the era of divided government. From 1900 to 1968, government was divided for only fourteen years, or a mere 20 percent of the time. Over the last 46 years, however, government has been divided for 36 years—or a whopping 78 percent of the time. Nixon dealt with opposition control of both chambers for the entirety of his administration; Reagan for his last two years; George H. W. Bush for his whole term; Clinton for three quarters of his. George W. Bush almost faced Democratic control of both chambers at the beginning of his presidency. Both he and Obama lost control of both houses with two years left in office.
A scenario where Clinton wins the Presidency and the Republicans retain control of both houses of Congress is fairly plausible. The changing nature of incumbency means there is a very strong chance the Republicans will retain the House of Representatives. The last House election had a 95 percent incumbency rate, despite Congress' overall approval rating floundering in the mid-teens. Only a small percentage of House seats are competitive these days, partly due to gerrymandering and partly to a startling urban-rural divide, with the Democratic base increasingly concentrated in cities.
To reclaim the House, Democrats would need to win thirty seats. In historical terms, this is a huge number. Since 1950, gains that large have occurred six times during midterm elections, when partisan waves often appear, but only twice in presidential years. The most likely scenarios, at this point, are modest to substantial gains, with the Democrats falling short of the necessary thirty seats.
The dynamics of the Senate races in 2016 would initially seem to favor the Democrats, because only 10 Senate Democrat seats are up for re-election, whereas the Republicans have to defend 24. But the Democrats will still have a lot of work to do to overturn the current Republican 54-seat majority. The conventional wisdom is that the Democrats would have to carry all three likely toss-up races: Illinois, Wisconsin and Florida, and at least one of four “lean-Republican” states: Pennsylvania, North Carolina, Ohio and New Hampshire, whilst defending two vulnerable states of their own, Nevada and Colorado—in order just to get to fifty seats.
Candidate selection matters, and could tip the balance. After the disasters of Sharron Angle and Christine O'Donnell in 2010, and Richard Mourdock and Todd Akin in 2012, the Republicans have been far more disciplined, with a better field of Senate candidates in 2014, and they have a number of strong incumbents in 2016.
In Nevada, Harry Reid’s retirement gives Republicans an opportunity to go on offense. Popular Republican Gov. Brian Sandoval cruised to reelection in November with 70 percent of the vote; Republicans have been urging him to consider a Senate bid.
In Wisconsin, Republican Sen. Ron Johnson has the ability to self-fund a campaign, is liked by the big-spending Koch brothers and may also benefit from the well-honed political machine of newly reelected Republican Gov. Scott Walker.
In Illinois, Republican Sen. Mark Kirk has worked hard to bolster his bipartisan credentials, backing immigration reform, gun control and environmental protections. His hard-fought battle to return from a debilitating stroke could also earn him sympathy from voters.
In Ohio, Republican Rob Portman is a fundraising powerhouse, has done little to stir controversy while in the Senate, and analysts on both sides acknowledge him as a strong candidate.
In New Hampshire, Democrats hoping to unseat Republican Kelly Ayotte think they have a strong candidate in popular Gov. Maggie Hassan; but Hassan may instead seek another term as governor. Even with Hassan in the race, Ayotte would have an even shot at winning, given the state’s narrow Democratic lean in presidential years.
Florida has trended Democratic in recent presidential cycles, but only by slight margins, so the race to fill a seat vacated by Marco Rubio would also be a potentially close one.
The extra dimension to all this is the extent to which Clinton's coat-tails can influence these tight races. But she is a polarizing candidate, looking to succeed a polarizing president, in a polarized electorate, in an era of divided government, where there hasn't been anything approaching an electoral college or popular vote landslide in a quarter of a century.
Whenever Clinton has run for office in the past (New York Senate and for the Democratic nomination) her national approval ratings have been sharply divided, a dynamic that threatens to trim Clinton’s impact down-ticket. Furthermore, many of the key Senate races are in states with traditionally high rates of vote-splitting: New Hampshire clocks in at 43.8 percent, Pennsylvania at 41.2 percent and at Nevada 36.8 percent. Therefore, it is likely that the “coat-tails effect” may give a boost to Democratic candidates in some races, but whether it turns out to be decisive is by no means a given.
Democratic presidential nominees are more often than not change candidates. Typically they represent the ascendancy of a new generation. The forty-three-year-old Kennedy offered youthful vigor, and proclaimed that “the torch has been passed to a new generation.” Jimmy Carter made a virtue of being an outsider. Bill Clinton offered a generational shift as the first baby-boomer in the White House. A similarly youthful Obama offered “Hope and Change” as well as a shift towards diversity.
Clinton of course offers a transformative candidacy as the first female president, but beneath this profound change element she is, in almost every other respect, the antithesis of the traditional Democratic presidential profile: She will be the oldest ever Democratic nominee, she has been a fixture on the national political scene for decades and she is a polarizing establishment figure.
Overall, therefore, the Republicans have a reasonable chance of holding on to their majorities in Congress—resulting in a unique election where Hillary Clinton makes history as the first Democratic President to win office with the Republicans controlling both Houses. Unless Democrats manage a blow-out, Clinton may address a largely hostile audience, including Republican majority leaders in the House and Senate, at her first state of the union address—the first time a newly-elected Democratic president has ever done so.