(CNN) — Former Vice President Joe Biden remains the biggest question mark of the 2020 primary season.

He leads his Democratic competitors in primary polls, has a number of potential surrogates waiting in the wings and has a clear general election polling lead over President Donald Trump in a cycle in which Democrats prize electability.

Yet despite those clear advantages, Biden hasn’t yet committed to throwing his hat into the ring.

So just how long can Biden wait to jump into the race, if that’s what he chooses to do?

The short answer: He still has time. The caveat: Historically speaking, most eventual nominees are already in the race at this point.

There have been 16 presidential primaries since 1972 in which an incumbent president was not running for re-election. The average nominee in these contests have either filed with the FEC or formally announced their candidacy by February 19 of the year before the primary.

Now, the spread of past nominees getting into the race is quite wide. A few got in very early like John McCain, who formed an exploratory committee on November 16, 2006. Others waited until the summer of the year before the primary.

If a candidate like Beto O’Rourke announced in the next few weeks, he’d be later than usual but still well within the normal range.

There’s little sign Biden is in any hurry to even come close to the average nominee, however. If Biden decides to run, he could jump into the race on the later end.

Another way to look at announcement dates is how nominees compared with the other candidates who ran for president in a given year. Some fields form later than others. Since 1972, 75% of eventual nominees were in the first half of those candidates who announced their run in a given primary. That is, most nominees showed little hesitation getting into the race compared to their competitors.

One possible reason for this: candidates who announce earlier can build better organizations, may be more confident about their runs and/or are in a better polling position than the average candidate. These advantages may allow them to end up being stronger candidates. Last cycle, initial Republican frontrunner Jeb Bush announced he was exploring a run in December 2014 and eventual nominee Donald Trump formed an exploratory committee in March 2015. Both were among the first in the Republican contest to get in the race.

CNN already counts 12 Democratic candidates for 2020 who have either formed an exploratory committee or have declared their candidacies and are still in the race. While it’s plausible that another 12 could get into the race, chances are that if Biden does get into the race he will have done so later than most other candidates.

There are, of course, a number of examples of candidates who did get in later in the year and did win their party’s nomination. Hillary Clinton in 2016 and Mitt Romney in 2012 waited until April of the year before the election to either announce their exploratory committee or their campaign. Notably, both were among the earliest candidates to get in the race in their given primaries.

The two nominees to file with the FEC or announce their candidacies the latest in a cycle since 1972 also went onto to become president. In the very slow forming field of 1992, Bill Clinton started his exploratory committee on August 16, 1991. He didn’t even formally announce that he was running until October 1991.

Perhaps, the most hopeful comparison for Biden is Ronald Reagan in 1980. Like Biden, Reagan had run for president twice before. Like Biden, Reagan led in the primary polls. Like Biden, age questions plagued Reagan. Like Biden, Reagan was hoping to take out an incumbent.

Reagan didn’t file with the FEC until May 18, 1979, which was far later than most of his competitors for the 1980 Republican nomination. He didn’t formally announce that he was in until November 13, 1979, which was later than all his serious competition.

Because Biden, like Reagan before him, is so well known and has previous campaign infrastructure in place, he likely can afford to wait longer to formally run than the average candidate.

Of course, for every Reagan, there are many candidates who enter late and fall short. Just in the past few cycles we saw Rick Perry in 2012 and Fred Thompson in 2008 squander strong early polling numbers once voters saw them in action. When you enter late, there’s less of a chance to fix problems with a campaign.

All told, the clock is ticking for someone like Biden. This is not some late forming field like it was in 1992 for Clinton. Biden probably wants to be in the race by June, which is when Reagan had filed with the FEC by and when the first 2020 primary debate is taking place.

The-CNN-Wire
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