The 2020 campaign begins in earnest next week in Florida, when Donald Trump officially launches his reelection bid. On June 26, 20 Democratic candidates and five moderators hold the first of two nights of debates. Where do things stand?

According to the polls, President Trump starts at a disadvantage. He has 44 percent approval in the Real Clear Politics average, with a net disapproval of 9 points. The most recent Quinnipiac poll has the major Democrats defeating Trump. The margins range from Joe Biden's 13-point victory to Pete Buttigieg and Cory Booker's 5-points. Another recent Quinnipiac poll has Biden leading Trump by four points in Texas. Private surveys of the Lone Star State also show a tight race. Trump polls very badly among suburban women, and the growth in suburban Texas has been extraordinary. Which spells trouble.

If the election were held today, a generic Democrat would defeat Donald Trump. What makes the predictions game difficult is that Election Day isn't for 16 months, and generic Democrats do not exist. Political conditions are bound to change, for better or worse, and voters once again will make a binary choice between the incumbent and a specific progressive alternative. That alternative might not be as flawed as Hillary Clinton. But he or she will have flaws.

Do the Democrats have more than a fighting chance? Absolutely. They've won the popular vote in all but one presidential election since 1992. And yet they would be foolish beyond belief to assume Trump is destined for a single term. President Trump can't beat a generic Democrat. Lucky for him he won't be facing one.

Trump holds the high ground of incumbency. Only once in the last century, in 1980, has the public ousted a party from the White House after just four years. Moreover, Trump is extremely unlikely to face a primary challenger, and at the moment the chances of an independent third-party candidacy are slim. At the outset of the contest, the economy is humming, the country is not in a major war, and there is no disruptive social unrest. This is a winning record.

What makes the 2020 election unique is the disjunction between objective conditions and presidential polling. Econometric models predict a Trump victory. "Mark Zandi, the chief economist at Moody's Analytics, has looked at 12 models," wrote Democrat Steven Rattner in the New York Times recently, "and Mr. Trump wins in all of them." The most famous qualitative model, Allan J. Lichtman's "13 keys to the presidency," also points to Trump's reelection.

The models aren't dispositive. Trump is such an unusual and unusually polarizing candidate that he underperformed the models last time around. He could do so again. Which makes his opponent decisive.

The Democratic field is weak. The frontrunner, Joe Biden, enjoys a solid national lead, but his margin in early states, especially Iowa, is narrowing.

And Biden has liabilities. They have been on display. His sloppy climate change plan not only reminded the public of his past plagiarism, it also included a carbon tax that will be easy for Trump to attack. His changing stance on the Hyde Amendment banning taxpayer funding of abortion, from support to opposition to support to opposition, was a disaster. It does more than suggest an opening for the "flip-flop" attack that worked against John Kerry in 2004. It also makes Biden vulnerable to the charge that he's caved to pro-abortion extremists.

Listening to the debut episode of the "Hacks on Tap" podcast with David Axelrod and Mike Murphy the other day, I was struck by how critical Axelrod was of Biden. Both strategists were skeptical of the former vice-president's ability to run the gauntlet. But Axelrod drew special attention to Biden's age, half-century in Washington, and poor track record as a presidential contender.

Iowa chose the winner in the last four contested Democratic nominations. Biden's history there is not reassuring. He didn't even make it to the caucuses in 1988, and came in fifth place 20 years later. "A look at polls taken at about this point in primary cycles since 1980 suggests that while Biden leads now, there's a pretty good chance he won't actually win the caucuses," writes Harry Enten of CNN.

Losing Iowa would dissipate the aura of inevitability and electability that surrounds Biden's pate. He'd be hard pressed to win in New Hampshire, where he faces two candidates from neighboring states. It's been a quarter of a century since a candidate lost two of the first three contests but went on to claim the nomination.

The Democrats don't have many good options beyond Biden. Bernie Sanders would turn the election into a referendum not on Trump but on socialism, breaking the Democratic Party and possibly drawing in an independent candidate. Elizabeth Warren has a story to tell, policy chops, and political seasoning, but Axelrod notes that she comes across as a professor delivering a TED Talk. Plus, the last three presidential nominees to come from Massachusetts all lost.

The last two Democratic presidents had youth, freshness, and cultural resonance. They were in their forties when first elected. The only first-tier candidate that approaches these criteria is Buttigieg. His problem is he's just 37 years old, mayor of the fourth-largest city in Indiana, and seems to have a problem attracting the support of minority voters. He'll have a breakout moment in the debates, for sure, but I won't believe the hype until I see it reflected in the polls. As for the other 19 candidates, yawn.

The 2020 election is shaping up to be complex and contradictory. A president who the models say should be running away with the race is under threat. A party that should be making its strongest case for a restoration is mired in impeachment talk, obsessed with slaking the appetite of left-wing interest groups, and offering a bizarrely expansive field of none-too-impressive challengers. A frontrunner whose strategy is to pretend he's already the nominee is slowly being brought down to Earth. And a country that never thought it could elect Donald Trump president might just do it again.