The Democrats descend on Columbus for the next episode of, “Who Wants to be President?” Twelve candidates will crowd the stage tonight, so expect heavy doses of interrupting, hand-raising, and podium chewing. The debate will be thin on substance–due to time constraints–and thick with drama. Expect an ideal made-for-television event.

The race has settled into a pattern that could persist until February’s Iowa Caucus. Former Vice President Joe Biden and Sen. Elizabeth Warren have distanced themselves from the pack. Given that they represent different elements of the party, they may be content to move forward without engaging one another unless Warren senses Biden is in the beginning of a free-fall. As impeachment proceeds against President Trump, the damage to Biden may continue to accelerate as his son’s business dealings are pulled into the spotlight. How Warren and the other candidates handle the situation will be telling.

Sen. Bernie Sanders is the only other candidate polling in double figures, but is recent health problems will cause voters to focus on what was already his biggest weakness–electability. His age, ideological inflexibility, and image were already problems for Sanders. Heart concerns might force even staunch supporters to reconsider his campaign.

The rest of the candidates are floundering at 5% or less in the polls. Pete Buttigieg has been unable, so far, to translate glowing media coverage and strong fundraising into significant electoral support. Kamala Harris and Beto O’Rourke, I think, have been considered and found wanting. Andrew Yang has traveled from obscurity to recognizability and he carries at least the possibility of appealing to moderates, independents, and some Republicans turned off by Trump. Statistically, he is the median candidate right now, which is remarkable, but I’m not sure he has the constituency to advance much more.

The most compelling theme for the debate, at least for this observer, will be the degree to which the Democrats continue to embrace an agenda that could allow moderate, independent, and suburban voters to see President Trump as the lesser threat to stability. The pull of the Twitter-Left has been persistent and irresistible to the field. The drive to please the progressives presents us with a band of candidates mostly devoted to the decriminalization of illegal border crossing, single-payer health care plans, broad support for the Green New Deal, significant restrictions on the right to bear arms, and the mainstreaming of transgenderism. The merits or demerits of these policy bents are not the issue. The issue is how college-educated, suburban parents might feel about these policies when they are attached to the presumptive nominee. Of the leaders, only Joe Biden can distinguish himself from this package of preferences. This is Biden’s greatest strength and weakness.