Since Barack Obama was elected president in 2008, there has been a slow uptick in Americans’ reported satisfaction with how things are going in the country.

You can see that in Gallup polling. Over the course of 2008, Gallup data indicated that, on average, 15 percent of Americans were satisfied with how things were going. (Those were optimistic people, given the state of the economy at the time.) In 2009, that jumped up to an average of 26 percent, before slipping back down into the upper teens by 2011. By Obama’s last year in office, the average was 27 percent, which carried into 2017, President Trump’s first year in office.

In 2018, the figure was over 30 percent for the first time since 2006. So far this year, the average has fallen slightly.

That chart doesn’t tell the real story. The real story is this.

During the 1990s, views of satisfaction among Democrats and Republicans generally tracked with one another. Starting in 2001, when George W. Bush became president, Democratic satisfaction tanked while Republicans remained confident with how things were going — at least until Bush was reelected. Then, the Iraq War and the economy submarined satisfaction even within Bush’s own party.

Satisfaction stayed low among Republicans during Obama’s two terms, recovering only once Trump won. Trump’s victory, though, prompted Democrats to suddenly see the direction of the country as increasingly unsatisfactory.

During Bill Clinton’s presidency, Democrats and Republicans differed in their satisfaction over how things were going by about 19 points on average. Under Bush, that gap soared to an average of 40 points. Under Trump? The average gap has been 45 points.

All of this may look familiar if you spent a reasonable amount of time paying attention to political data. It largely mirrors another metric that is in the news more regularly: a president’s job approval.

Clinton’s approval numbers ranged from 37 to 73 points over the course of his presidency. Bush’s varied from a low of 25 to a high of 90 percent after the 9/11 attacks. Obama’s range was narrower, from 41 to 66 percent. Trump’s has been essentially flat, no lower in Gallup polling than 36 percent and no higher than 45 percent.

Why? Again because of partisanship. Democrats like Trump much less than Republicans liked Clinton and even less than Republicans liked Obama. Those views have been static: Democrats have always disliked Trump and Republicans have always liked him, meaning that views of political partisans have mostly been locked in place since he took office.

Bush and Obama got honeymoon periods from the opposition (however small), and Bush had that 9/11 surge. Trump just hasn’t moved.

Over the course of Clinton’s two terms, Gallup polling found an average spread between the parties of 55 points. During Bush’s terms, the gap averaged 61 points. During Obama’s, it was 71 points. So far in Trump’s? The gap has averaged 79 points.

All of this brings us to the question we’re here to answer: Does this new reality — or, really, this evolved reality — suggest that new mechanics will be in play in 2020?

On Tuesday, the New York Times looked at the history of successful Democratic moderates in political campaigns. Even in the 2018 Democratic wave, they argue, more moderate candidates had more success in congressional campaigns. Plenty of invisible asterisks litter the piece, but the subtext is pretty clear: Democrats will probably have better luck in 2020 if they nominate a more moderate candidate.

That’s good news for the current leader in that race, former vice president Joe Biden. While his policy positions aren’t exactly centrist, Biden has been overt in embracing a less-liberal agenda than his competition. He has been rewarded with strong support from moderate Democrats and has enjoyed a lead since getting into the race.

There are a lot of factors that overlap in Biden’s support, so many that it’s hard to suss out the importance of his more-moderate policies. That support from moderates, for example, correlates to stronger support from black Democrats who, as a group, tend to hold more moderate policy positions. Biden’s position in the polls is also bolstered by the sense that he has the best chance of beating Trump in a general election, a sense that may derive in part from his taking less partisan positions on issues. It’s a melange.

What we want to evaluate is that last link: Do his more moderate positions mean he has a better chance of winning? The Times suggests sort of shruggingly that, yes, probably. Which brings us back to those graphs.

Democrats hate Trump. Not all of them, of course, but most of them. It’s a large part of why there was a blue wave last year. The Times’s analysis suggests that candidates who opposed Medicare-for-all — a central policy position of the more-liberal wing of the party — did a few points better than those who supported it. But it doesn’t suggest that a Medicare-for-all position cost the Democrats any races.

The Post-ABC News poll released over the weekend found that Democratic primary voters are more likely to see beating Trump as important than nominating a candidate who shares their policy positions. There are gaps among demographic groups on that question — younger voters, men, nonwhite Democrats and those without a college degree are more likely to view policy positions as important. Overall, though, beating Trump takes primacy.

There was a theory popularized by Sen. Ted Cruz (R-Tex.) in 2016 that went something like this: Nominate a hard-right conservative, and more-moderate Republicans would vote for that candidate anyway. But conservatives who had stayed home when the party’s nominees were John McCain and Mitt Romney would surge to the polls. That theory ended up playing out to Trump’s benefit, though the surge was less from traditional conservatives than more broadly disaffected Republicans. Many moderate Republicans, though, came out to vote for him anyway.

The countervailing theory to the “a moderate is the safer bet for Democrats” is a variant on that Cruz theory. Nominate someone who energizes less-frequent voters — like voters of color or younger people — and you’ll get the same surge. Other Democrats, loathing Trump, will hold their noses if needed and vote for whichever Democrat is nominated.

Remember: Most Democrats now identify as liberal. That’s a shift that has been slowly happening in the party, with self-identified liberals passing moderates during Obama’s tenure. More liberal policy proposals, then, probably square more solidly with the party than they once would have.

The question here really comes down to energy.

Millions of voters who had backed Obama in 2012 stayed home in 2016, more than half of them nonwhite. Those voters were likely heavily in states that Hillary Clinton carried anyway, but the margins in states such as Pennsylvania and Michigan were so narrow that turning them out might have made the difference.

One theory of why Clinton lost, why those voters stayed home, is precisely that she didn’t inspire sufficient energy with Obama voters. She, like Biden, was supported more heavily by black Democrats in the primary, but black turnout in 2016 declined from 2012. More liberal Democrats, many of whom had backed Sen. Bernie Sanders (I-Vt.), probably weren’t as energized to support Clinton as they might otherwise have been, given her more-moderate record. Overlay expectations that Clinton would win, and you get Trump’s narrow electoral college victory.

There’s a lot of partisan energy reflected in those graphs of satisfaction and presidential approval — often negative energy. Democrats desperately want to beat Trump. A CNN poll released Tuesday shows that independents largely oppose Trump, too: Two-thirds of independents think Trump doesn’t deserve a second term, joining nine in 10 Democrats and even a fifth of Republicans. Numbers like that suggest that Trump himself may be all of the motivation needed for Democrats to win in 2020.

Perhaps a moderate Democrat would fare slightly better than a more liberal one, spurring more independents to go to the polls. In an environment this polarized, though, turning out Democrats to oppose a president they despise seems like an easier prospect than historical data might capture.