Back in the 2016 campaign, I noticed a pattern that could be called "the spotlight paradox:" whenever the focus was on one candidate, the other candidate benefitted. Here's what I wrote in late October of that year: "When we are talking about taxes, tapes and tweets, the polls move in Hillary Clinton's favor. When emails dominate the headlines, Clinton's lead shrinks." I attributed it to the fact that the race for the White House was dominated more by personality than policy. And, to the fact that with both candidates so deeply disliked, the candidate who was out of the spotlight benefitted by, well, being quiet. Out of sight, out of mind was actually helpful. 

There's something of a spotlight paradox happening in the Democratic primary this year. The candidates who have spent time under the bright lights have wilted, while those sitting in its shadow have risen. 

Why is this? Democrats don't suddenly dislike the candidates who have undergone the scrutiny that comes with front runner status. What they do dislike, however, is vulnerability. For many Democratic voters, President Trump is an existential threat. As with any existential threat, the most important question is who/what can beat it. In 2019, a candidate's ideology isn't as important as his or her ability to take a punch. And be able to punch back. 

Biden started the race as the guy best suited to do just that. He started the race as the affable frontrunner, who had a long history with the party and a solid relationship with the country's first African-American president. What he lacked in energy, he made up for in electability. Who better to win back those Rust Belt states than good old "Scranton Joe." 

But, once in the spotlight, or more specifically, under the debate stage lights, Biden looked anything but invincible. His performances in the first two debates were shaky and uneven. He spent most of the summer on his heels, defending (or changing) past policy positions and struggling to raise money. 

From May to November, Biden's share of the Democratic vote dropped 10 points in Monmouth polls. In Quinnipiac surveys, he dropped nine points from June to October. 

As Biden slipped, Sen. Elizabeth Warren started to rise. She was attracting big crowds in Iowa, raising lots of money online and getting a second look from voters and pundits who had written her off earlier in the year as she struggled to explain her decision to take a DNA test to prove her Native American ancestry. By early October, the RealClearPolitics average showed Warren narrowly overtaking Biden, 26.6 to 26.4 percent. But, as she struggled to adequately explain how her plan for a Medicare for All system would work, voters started to get worried. Could the woman with the "plan" for everything, really be this unprepared to answer questions about a central issue in the campaign? And, if so, wouldn't Trump exploit this?

Since reaching that high on October 8, Warren has begun a steady downward trajectory. The most recent RCP average pegs her vote share at 12 percent —13 points behind Biden.

As Warren slipped, anxious Democrats began to cast about for a candidate who would be steadier and less flawed than Biden or Warren had proven to be. And, right on cue, comes South Bend Mayor Pete Buttigieg. He has been aggressive in the debates, steady on the stump and has surged into a big lead in Iowa. Since mid-October, Buttigieg has risen eight points in the RealClearPolitics average. The big ole spotlight is now trained directly on him and on his biggest weaknesses, namely his inability to attract voters of color. 

As Buttigieg undergoes his 'stress test,' there's another candidate just outside of the spotlight who is well-positioned to take advantage of this moment: Sen. Bernie Sanders. While we were all focused on Warren's crashing, and Buttigieg's rise, Sanders has been slowing moving up in the polls. The RealClearPolitics average puts him in second place nationally, and just slightly behind Buttigieg in Iowa and New Hampshire. He's also holding a good position in Nevada. This, despite the fact that he spent much of the fall recuperating from a heart attack. 

Meanwhile, with the spotlight off of him, Biden has recovered his lead in the national polls and is essentially tied for second place in Iowa. While many in Democratic circles are convinced it's only a matter of time before Biden collapses, he's still holding on to a decent lead in national polls and a solid one in South Carolina. He has been able to weather bad headlines about his son and Ukraine, while also taking swipes at Warren's health care plan and, most recently, at President Trump's low standing with world leaders.

My son is a big fan of Japanese anime and comics. One of his favorite characters is named "One Punch Man." He's a regular looking guy with one amazing superpower: he can defeat any man or machine or monster with just one punch. In politics, however, there is no such thing as a "One Punch Man." The best one can hope for is a candidate who can withstand the inevitable blows that will come, while also being able to land a couple of punches on their opponents as well. 

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