The Justice Department says Rep. Chaka Fattah (D-Pa.) and four of his associates have been charged with participating in a racketeering conspiracy. (Reuters)

So far this primary season, we haven't seen the anti-Washington mood that is raging at the presidential level filter down to the congressional level. In fact, you could argue we still haven't seen that, even after Rep. Chaka Fattah (D-Pa.) lost his primary Tuesday night and earned the unwanted distinction of being the first incumbent to go down in 2016.

That's because Fattah's race was less about his two decades in Congress and more about the very serious criminal charges he faces.

In late July, prosecutors slapped the Philadelphia congressman with 29 charges ranging from bribery and money laundering and bank fraud related to a $1 million loan in his 2007 Philadelphia mayoral bid. Four other political associates of his, including top aides, were on the indictment. In short, Fattah is in a legal mess right now. If we had to pick just one incumbent expected to go down this cycle -- no matter the national mood -- we might have picked him.

It's true Fattah hasn't lost a race, or even had a primary challenger, since 1994. He's well known in the heavily Democratic Philadelphia area, which makes up 90 percent of the district's registered voters. But as he was campaigning for a 12th term, he was also preparing to stand trial for the charges next month. (Fattah has said the charges against him are frivolous.)

In a sign of how quickly his fortunes changed with the charges, Pennsylvania's current governor, former governor and Philadelphia's mayor all endorsed his opponent -- longtime state Rep. Dwight Evans, the strongest of three primary challengers. On Tuesday, Fattah fell to Evans, 43-36, with 93 percent of precincts reporting.

It was a race that surprised few political watchers, even in this unpredictable campaign.

Despite the anti-Washington sentiment that has appeared to grow in recent years, incumbents still very rarely lose primaries. House Majority Leader Eric Cantor (R-Va.) was one of just four House incumbents and one senator who lost primaries in 2014 -- out of nearly 470 races -- according to the Campaign Finance Institute. That number was very much in-line with recent history.