Let me begin this preview with a note of humility: when the 2012 election season began, it was widely reported that President Obama was going to have serious trouble getting reelected, and that the Republicans were odds-on favorites to recapture the U.S. Senate. As we know, President Obama won reelection by margins that, when all the votes are counted, will not be that far off his sweeping 2008 victory, and Republicans not only failed to take the Senate but actually lost a net of two seats.

The preceding disclaimer should demonstrate that likelihoods are not guarantees, and that any preview of an upcoming election two years out is a risky proposition. Who could have foreseen, in 2010, that Republicans would lose not one but two Senate races because their nominees in those races would make idiotic comments about rape?

That said, all indications right now point to 2014 being a tough year for Democrats and a good one for Republicans.

First, although Democrats did spectacularly well in 2012, there were still some indicators that should cause concern. President Obama became the first president in U.S. history to win reelection with a smaller percentage of the popular vote than he won in his first election, and only the third reelected president to receive fewer electoral votes in his reelection campaign. The first was James Madison in 1812, in the midst of an unpopular war with Britain. The second was Woodrow Wilson in 1916, but that comes with a big caveat: his sweeping 1912 victory was due entirely to President William Howard Taft and former President Theodore Roosevelt splitting the GOP vote and, thereby, helping deliver 40 states to Wilson. And although Democrats did pick up a net of eight seats in the U.S. House, they left another dozen on the table that they could have won if they had performed just a percentage point or two better. So, yes, the Democrats did well in 2012, but their performance was not nearly as strong as their results in 2006 and 2008, when there were true Democratic waves.

Secondly, just as in 2010, Democrats are far more exposed in U.S. Senate races than Republicans are. The Democratic class of 2008, which netted their party an eight-seat pickup in the Senate, faces its first reelection test. Democrats are defending 20 of the 33 seats up for election, and of the 13 Republicans who are up, it is hard to find even one who looks vulnerable now. Perhaps Senate minority leader Mitch McConnell (R-Ky.) may face a tough race; he struggled in each of his last two elections and may be ripe for an upset, but even that is a longshot for Democrats; it is a certainty that McConnell will raise stunning amounts of money. But no fewer than eight Democratic Senators will face difficult challenges in 2014, and perhaps as many as 10. If Republicans net six seats, they will reclaim the chamber. It is true that Democrats faced longer odds in 2012 but still prevailed—and in fact increased their majority in the Senate. How likely is it that they can defy the odds two cycles in a row?

Third, Democrats will have a hard time hanging on to a number of the U.S. House seats they captured in 2012. Of 33 House races decided by less than six percentage points this year, Democrats won 20 and Republicans only 13. Additionally, Democrats won two seats—in Florida’s 26th District and Illinois’ 8th District—by double digits, but this was largely due to the implosion of Republican incumbents David Rivera and Joe Walsh, respectively.

We have seen, as we saw in 2010, that Democratic turnout in midterms can lag significantly as compared to presidential election years. If Democrats fail to turn out their voters in the 2014 midterms, it is not hard to see Democratic losses of 10-20 House seats and 4-8 Senate seats.

Couple the potential for a falloff in Democratic turnout with the likelihood that Republicans will continue to obstruct the process—thereby denying President Obama and the Democrats significant victories—and the prospects for a Republican turnaround in 2014 look strong.

Then there’s history. Since the founding of both of the current major political parties, there have been 11 midterm elections under presidents serving their second terms. In 10 of those 11 elections, the president’s party has lost seats in both the House and the Senate—on average, 34 House seats and six Senate seats. The only exception was the 1998 midterm election, in which Republican investigations of President Bill Clinton backfired and cost the GOP a modest net loss of four House seats. Let’s have a look:

1874
President Ulysses S. Grant (R)
Republicans lost 93 House seats
Senators were not elected by popular vote at this time.

1906
President Theodore Roosevelt (R)
Republicans lost 28 House seats
Senators were not elected by popular vote at this time.

1918
President Woodrow Wilson (D)
Democrats lost 19 House seats and 6 Senate seats

1926
President Calvin Coolidge (R)
Republicans lost 10 House seats and 6 Senate seats

1938
President Franklin D. Roosevelt (D)
Democrats lost 71 House seats and 6 Senate seats

1950
President Harry S. Truman (D)
Democrats lost 29 House seats and 6 Senate seats

1958
President Dwight D. Eisenhower (R)
Republicans lost 48 House seats and 13 Senate seats

1966
President Lyndon B. Johnson (D)
Democrats lost 47 House seats and 4 Senate seats

1986
President Ronald Reagan (R)
Republicans lost 5 House seats and 8 Senate seats

1998
President Bill Clinton (D)
Democrats picked up 4 House seats and broke even in the Senate

2006
President George W. Bush (R)
Republicans lost 30 House seats and 6 Senate seats

In short, every indicator demonstrates that Democrats should lose big in the upcoming midterm elections. As we saw this year, and in 1998, what is expected to happen doesn’t always necessarily occur. But Democrats must be prepared to work very hard if they want to avoid the usual midterm losses that almost always happen to the party of a president at his second midterm.