Mayor Pete Buttigieg and Senator Bernie Sanders will be standing on either side of former Vice President Joe Biden in tonight’s debate, which begins at 9 p.m. ET.

Buttigieg, at age 37, is the youngest Democratic primary candidate and will likely try to highlight the generational differences between himself and Sanders and Biden.

It’s possible that the moderators could bring up the fact that Buttigieg won a national essay contest when he was a high school senior by writing about Sanders. He called the Vermont congressman “impressive” and praised him for holding true to his values.

Here’s what you need to know.

Pete Buttigieg Profiled Senator Sanders for a Scholarship Essay Contest Run by the Kennedy Family

Pete Buttigieg wrote about Senator Sanders for the Profile in Courage Essay Contest. It is an annual contest run by the John F. Kennedy Library Foundation. Students are asked to write “about a current political issue at the local, state or national level and an elected official in the United States who is acting courageously to address that issue.” At the time, Sanders was the only independent congressman on Capitol Hill.

Buttigieg explained in his autobiography Shortest Way Home that he initially had planned to write about Rep. Carolyn McCarthy of New York, who ran for Congress after her husband was shot and killed. Buttigieg said he had nearly finished the essay before realizing that the previous year’s winner had selected Rep. McCarthy as the subject, and he had to start over.

Buttigieg wrote in his memoir that he decided to switch his focus to Senator Sanders, whom he “found even more interesting, if a little more edgy politically… ‘Socialist’ was the dirtiest word in politics, yet he won because people saw that he came by his values honestly. Regardless of whether you agreed politically, it certainly seemed like a profile in courage to me.”

Buttigieg was chosen for the $3,000 scholarship prize among an application pool of 600 essays, according to a news release at the time. He attended an awards ceremony at the JFK Library in Boston, where he posed for a picture with Caroline Kennedy and met Senator Ted Kennedy.

Buttigieg Praised Sanders For His Ability to ‘Bring People Together’ & For Refusing to Give In to Cynicism

Pete Buttigieg, then 18 years old, began his essay lamenting what he saw as a growing trend of lawmakers shying away from sharing their true beliefs out of fear of losing voters. He wrote that Republicans and Democrats tried to get elected “by not offending anyone rather than by impressing the voters,” which actually made voters feel more cynical about the entire process. Buttigieg said that Senator Sanders broke the mold for refusing to act like this.

“Sanders’ courage is evident in the first word he uses to describe himself: ‘Socialist.’ In a country where Communism is still the dirtiest of ideological dirty words, in a climate where even liberalism is considered radical, and Socialism is immediately and perhaps willfully confused with Communism, a politician dares to call himself a socialist? He does indeed. Here is someone who has ‘looked into his own soul’ and expressed an ideology, the endorsement of which, in today’s political atmosphere, is analogous to a self-inflicted gunshot wound. Even though he has lived through a time in which an admitted socialist could not act in a film, let alone hold a Congressional seat, Sanders is not afraid to be candid about his political persuasion.

Buttigieg went on to say that Senator Sanders was able to use his position as an independent to try to bridge the gap between Republicans and Democrats.

“Sanders has used his unique position as the lone Independent Congressman to help Democrats and Republicans force hearings on the internal structure of the International Monetary Fund, which he sees as excessively powerful and unaccountable. He also succeeded in quietly persuading reluctant Republicans and President Clinton to ban the import of products made by under-age workers. Sanders drew some criticism from the far left when he chose to grudgingly endorse President Clinton’s bids for election and re-election as President. Sanders explained that while he disagreed with many of Clinton’s centrist policies, he felt that he was the best option for America’s working class. Sanders’ positions on many difficult issues are commendable, but his real impact has been as a reaction to the cynical climate which threatens the effectiveness of the democratic system. His energy, candor, conviction, and ability to bring people together stand against the current of opportunism, moral compromise, and partisanship which runs rampant on the American political scene. He and few others like him have the power to restore principle and leadership in Congress and to win back the faith of a voting public weary and wary of political opportunism. Above all, I commend Bernie Sanders for giving me an answer to those who say American young people see politics as a cesspool of corruption, beyond redemption. I have heard that no sensible young person today would want to give his or her life to public service. I can personally assure you this is untrue.”

You can read the full essay here.

Buttigieg Was Criticized For Appearing to Compare Sanders to Trump During a Speech

Just now – I asked ⁦@PeteButtigieg⁩ about some Sanders supporters including ⁦@RoKhanna⁩ upset that Buttigieg suggested Sanders and Trump supporters were motivated by the same economic anxieties. Here’s what he said: pic.twitter.com/UTInTBzHHl — Josh Lederman (@JoshNBCNews) April 22, 2019

Mayor Pete Buttigieg faced some backlash back in April when he compared people who supported Senator Sanders during the 2016 election to voters who backed President Trump. Buttigieg had told a crowd in New Hampshire that he could understand that frustrated voters would “want to vote to blow up the system” and that both Sanders and Trump represented that type of mindset.

Amid criticism, Buttigieg later clarified that all he meant was that Sanders and Trump were both considered political outsiders. They had different viewpoints on how to achieve change, but the point was that neither one of them are considered part of the Washington “establishment.”

Buttigieg told NBC News, “My point is that people have been motivated to want to blow up the establishment. And Bernie Sanders and Donald Trump represent radically different ways of doing that. But I think part of how each of them was able to get some appeal was by speaking to the frustration that so many Americans have with anything perceived as the establishment, anything seen as being committed to the political and economic systems that have been prevailing really for my entire life.”