And then there were 16. On Monday night, U.S. Rep. Eric Swalwell of California announced in an interview on “The Late Show with Stephen Colbert” that he was joining the Democratic melee for president.

Swalwell is a long-shot candidate whose bid may leave you scratching your head, but he has a history of going it alone electorally. In 2016, for example, he was the only congressional Democrat to support former Maryland Gov. Martin O’Malley’s failed presidential campaign.

And if Swalwell somehow wins the Democratic nomination in 2020, it won’t be the first time that he’s pulled off a shocking political upset. In 2012, at age 31, he defeated Rep. Pete Stark, who had served in Congress for 40 years, by 4 percentage points in a Democrat-vs.-Democrat general election. (It was the first election cycle under California’s top-two primary system, whereby the top two finishers, regardless of party, advance to the general election.) A powerful member of the House Ways and Means Committee, Stark had helped usher in significant health care reforms and had the backing of both President Barack Obama and House Minority Leader Nancy Pelosi. But Swalwell swooped in, arguing that the incumbent, who had been described as “a loose cannon,” had worn out his welcome and that it was time for a fresh face.

That success may not carry over to the 2020 Democratic primary, however. Swalwell’s 2012 win was likely aided by redistricting (only about 40 percent of Stark’s old district was part of the new one) and the new voting system, which meant that Republicans’ votes were up for grabs in the all-Democratic general election. An analysis of the returns by FiveThirtyEight suggests that Swalwell got a lot of help from Republican voters. In areas where Republican presidential candidate Mitt Romney did well, Swalwell did well too. Swalwell also lost the precincts that went strongest for Obama. That helped Swalwell pry the seat from Stark, but that doesn’t necessarily translate as an advantage in 2020, since few Republicans are likely to vote in the Democratic presidential primary.

Since 2012, Swalwell has performed and voted as one might expect of a Democrat in a pretty blue district. He defeated his Republican opponent in 2018 by 46 percentage points — right how you’d predict a generic Democratic candidate running in that district in 2018 to do. In Congress, he is a mainstream liberal, albeit slightly less so than the median Democrat, according to DW-Nominate, a metric that measures the ideology of all senators and representatives based on their voting records. When President Trump has expressed an opinion on a proposal before Congress, Swalwell has voted against Trump’s preference more than 80 percent of the time since the beginning of the administration, though that’s a bit lower than we’d expect based on Trump’s 2016 performance in Swalwell’s district.

Perhaps unsurprisingly, Swalwell hasn’t gotten a lot of attention as a potential presidential candidate. Only four pollsters have included him in early 2020 polls, and he has garnered only 0 or 1 percent in them. He has yet to bag any major endorsements. But Swalwell is reasonably adept at drawing attention to himself — he is a prolific user of social media and is a frequent guest on cable news shows, where he has used special counsel Robert Mueller’s investigation into Russian interference in the 2016 election to criticize Trump (even after Attorney General William Barr wrote a letter to Congress saying that the president’s campaign was not involved). Over the past few months, he has gotten roughly as much cable news coverage as Julian Castro or Tulsi Gabbard has, according to an analysis of the relative amount of coverage each candidate got on CNN, Fox News and MSNBC based on data from the TV News Archive. That’s not bad for someone who wasn’t a presidential candidate at the time, but it’s still many times less than the coverage received by the top-tier candidates.

The problem for Swalwell is that even though he theoretically has several advantages as a candidate, he’s entering the race after others have staked out that ground. As a Californian, he could have home-field advantage in the most delegate-rich state, plus access to its deep-pocketed Democratic donors. But Kamala Harris, the state’s junior senator, is also in the race. As a 38-year-old whose rhetoric speaks to millennial concerns (he founded Future Forum, a group of Democratic U.S. House members who are focusing on millennial concerns and touts that he is still living with student debt), Swalwell could find a natural constituency among young voters. But Pete Buttigieg, who is a millennial, is also trying to appeal to those voters, and polls show that Bernie Sanders is doing well with this demographic as well. And while Swalwell has experience winning voters of different races (his district is about a third non-Hispanic white, about a third Asian and about a quarter Hispanic), it might not give him much of an advantage in a primary field that has such a diverse array of candidates.

But there is one trump card in Swalwell’s hand: He was born in Iowa, the first state to hold a presidential nominating contest. Swalwell didn’t spend his whole childhood there, but he is clearly putting a lot of his eggs in Iowa’s basket — he has visited the state at least 16 times since early 2017. Unfortunately for him, though, there’s not a lot of evidence that having Iowa roots helps you in the Hawkeye State. Former U.S. Rep. Michele Bachmann of Minnesota was born in Iowa but finished sixth in the 2012 Iowa Republican caucuses. But Swalwell’s frequent visits there do appear to be paying off in one sense: 29 percent of likely Democratic Iowa caucus-goers know enough about Swalwell to form an opinion of him, according to the most recent poll of the state; that’s higher than in either of the two national polls to ask about his favorability so far. However, in the horse-race question of that same Iowa poll, Swalwell received only 1 percent of the vote. He’ll need to put in a lot more work if he wants to avoid Bachmann’s fate of dropping out after flopping on caucus night.

Rep. Eric Swalwell on his 2020 presidential bid

Dhrumil Mehta contributed research.