(CNN) Former Vice President Joe Biden officially jumped into the 2020 presidential race on Thursday -- and his candidacy is perhaps the most analytically perplexing of any of the Democrats. He's probably got the best chance of any Democrat running to win the nomination, but the other candidates combined have a significantly better shot than he does.

What makes figuring out Biden so confusing? For every argument in favor of his bid, there's one against it. Let's get into it!

The case for Biden: His polling lead is real

Biden has averaged about 28% in the national polls over the last month and about 30% since the beginning of the year . It's easy to now scream "name recognition" and point to Jeb Bush, who fell apart four years ago in the race for the Republican nomination. But comparisons like that are unfair from a numbers context.

Looking back at polling since 1972 , well-known candidates who average 30% in the first half of the year before the primary win their primaries about 40% of the time. Bush, for reference, was polling at half the level Biden has been nationally.

One way you can know Biden's advantage is not just about name recognition is to look at the early states where voters should be paying the most attention. Over the first 4.5+ months of 2019, Biden's averaged 26% in Iowa, 24% in New Hampshire (where he is fighting against Sens. Bernie Sanders and Elizabeth Warren, who represent next-door states), 26% in Nevada and 36% in South Carolina. Across all four, he's averaged 28% since the beginning of the year.

Biden's fairly strong horse-race numbers are backed up by having the best favorability ratings in the Democratic field. And keep in mind, he's also polling better than Sanders or Warren, who have similarly high name recognition.

The case against Biden: He may have an activist problem

Biden is supposedly going to trot out a bunch of endorsements following his announcement. That's a good sign for the former vice president, given endorsements are usually correlated with primary success. Still, Biden hasn't shown anywhere near the strength in the endorsement primary that you might expect from someone who was elected to the US Senate more than 45 years ago.

Additionally, party activists in the early states seem to be leaning away from Biden, according to a study by University of Denver Professor Seth Masket. Only about a fifth of them are currently considering backing Biden. That's down considerably from the end of last year. (Note: I've discussed the potential flaws in using this study to project the primary before.)

The split is, in a way, reminiscent of the 2016 campaign. In that cycle , Bush held a nominal advantage among elites (i.e. office holders). Activists, however, were not fans of his. On the other hand, Donald Trump was the opposite. Elites didn't like him, while he was reasonably well liked in surveys of activists.

Biden's certainly hoping for a different result in 2020 than 2016, if there ends up being a split between activists and elites. Biden will need to have good support from union activists

If I were Biden, though, I'd worry that party apparatus isn't more in my corner.

The case for Biden: No top tier candidates are appealing to his base

I've written previously on how the Democratic Party is more moderate and older than you probably think it is. About 50% of Democratic voters call themselves moderate or conservative, which is about the same percentage that are at least 50 years old. Most Democratic candidates running this year don't seem to recognize that fact.

We've seen a Democratic field in which the candidates seem to be falling over each other to move further left , where the youngest Democrats are

Biden, meanwhile, is sitting all alone in his base. In a Monmouth University poll released earlier this week, he had a 19-point advantage over his nearest competitor with Democrats who called themselves moderate or conservative. He was up by 18 points among those who were at least 50 years old. A Quinnipiac University poll released last month (that had Biden in a similar overall position) gave him even bigger advantages with more moderate and older voters.

Now, Biden does trail with the youngest and very liberal Democrats. But they make up a minority of the party, and Biden's competitors are splitting that vote.

The case against Biden: His age problem

A lot of the attacks on Biden are, from an electoral angle, silly. Going after Biden for his lack of liberal wokeness , for example, seems destined to fail, given that the polling shows that Democrats want the party to move in a more moderate direction

Biden's age is more likely to derail his candidacy. An NBC/Wall Street Journal poll taken in late February showed that only 33% of Democrats would feel enthusiastic or comfortable nominating someone older than 75.

2013 study by political scientists Jens Hainmueller, Daniel J. Hopkins and Teppei Yamamoto came to a similar conclusion. Candidates older than 75 were penalized compared to younger candidates.

Now, could it be the case that Democrats are merely opposed to an older candidate in the abstract? Sure. The yearning for a younger candidate may be a weak preference that could be overturned based on who is running. After all, Biden and the even older Sanders are doing well in the polls right now.

Still, it's important to note how low 33%, the percentage of people who would feel comfortable or enthusiastic supporting someone over the age of 75, is. It's about equal to the percentage of Democrats who would be enthusiastic or comfortable backing an evangelical Christian or businessman. I've pointed out before that Democrats seemed to be penalizing candidates in early polls who were mainly known as businessmen.

The fact that Biden is called "Sleepy Joe" by Trump and is known to make gaffes may open the age question more than polling indicates right now.

The case for and against Biden: His appeals on electability

If Democratic voters continue to think Biden is the most electable, he's in business.

Electability advantages, though, can be fleeting. Why? When you lose an individual caucus or primary, you seem less electable.

Consider the case of the crowded 2004 Democratic field. Like this one, it lacked a dominant frontrunner. Before the Iowa caucuses, Howard Dean led in the national polls and was seen as the most electable. Once he lost in the early contests to John Kerry, though, Kerry was seen as the most electable.

If voters nationally see Biden start losing early contests, they will probably turn on him very quickly.

Final thought

Biden's candidacy is going to be a great political science experiment. If he wins, it'll be the second time in four years when an early poll leader won, despite many dismissing his candidacy. If he loses, expect a lot of "told you so" moments from those who think Biden's time has passed.