Mitt Romney somehow wins the electoral college in 2012, but loses the popular vote to Pres. Obama. Obama, who was still decently popular at the time of the election (roughly 50% - if not more so), speaks about calm and supporting Romney, who many, especially in the black community, feel is illegitimate. He gains a great deal of goodwill from the American people with his handling of such a stunningly difficult defeat (Ohio proved the tipping point, with the President losing the state by a mere thousand votes or so) and leaves office with soaring approval ratings.
Romney comes in, instantly finds senate Democrats combative (after two years of House obstructionism, they're ready for payback ... plus, Republicans couldn't grab the senate). The fiscal cliff happens, as there is no deal reached between House Republicans, Senate Democrats and the White House. The economy is off to a shaky start in 2013 and things spiral a bit out of control.
Romney finds it difficult connecting with the American people early in his presidency, which hurts his overall image. His popularity isn't bad - but rarely eclipsing 50% by mid-2013. Eventually, the economy slowly begins to recover from the initial shock of the fiscal cliff, but its growth is tepid and Americans become increasingly wary of the overall economic situation.
The NSA leaks still happen, and Romney gets a bulk of the blame, even though it's evident the issue played out under both Bush and Obama. The IRS scandal isn't nearly as wide, though there are rumors that the IRS did target leftist groups under Bush (and some conservative groups under Obama).
Romney struggles to get things done in his first two years. He's never successful at repealing Obamacare, which slowly gains acceptance into the mainstream - and his Tax Relief Act is dead on arrival once it reaches the Senate. With his hands tied, and the economy shaky, the Republicans nearly lose the House in 2014 and fail to make gains in the U.S. Senate, even though they had a favorable set up.
Much of the media at this point starts suggesting Romney is a one-term president. His approval, much like Obama's in 2011, slips to the low 40s.
He's not entirely unpopular - but he's in that gray area where his reelection odds are iffy, especially in the new political landscape of hyper partisanship.
Obama, however, is seen as widely popular again outside the lens of the Washington media. He helps stump for midterm Democrats, works on an initiative to help black male youths, and hints at potentially running against Romney again in 2016.
With polls in mid-2015 showing Obama soundly beating Romney, speculation really heats up - especially when Hillary announces she won't seek the presidency. Finally, after much hemming and hawing, Obama announces his plans for reelection.
He faces no real challenge in the primaries, even though former Vice President Biden showed interest.
Romney faces no real Republican challenger, wrapping up the nomination, and entering the election year with a 45% approval rating.
In the end, key shifting demographics deliver the White House back to Obama, who defeats Romney with over 300 electoral votes and a margin of three-points in the popular vote.
Romney leaves office respected for his attempt, but often considered ineffective in guiding the country through the partisanship divide. Obama steps in with a new term of his own - and growing international challenges.