Democrats' last House win locks in brutally small GOP majority

• Democrats are already formulating ways to kill party-line GOP votes and force Republicans to pursue a bipartisan approach to governance.

Driving the news: Rep. John Duarte (R-Calif.) told Axios he conceded to Democratic challenger Adam Gray after nearly a month of vote-counting.

• Gray, who won by under 200 votes, declared victory in a statement saying he is "honored to become the Congressman-elect for California's 13th district."
• House Democratic caucus chair Pete Aguilar (D-Calif.) boasted in a statement on Gray's win, "Republicans now have no room for error because of their historically narrow margin."

By the numbers: Gray's victory means Republicans are set to have 220 seats to Democrats' 215 when the 119th Congress is sworn in on Jan. 3.

• To make matters worse for House Republicans, Trump has selected Reps. Michael Waltz (R-Fla.) and Elise Stefanik (R-N.Y.) as his national security advisor and ambassador to the United Nations, respectively.
• Both of their seats, along with that of Rep. Matt Gaetz (R-Fla.), who resigned in pursuit of a short-lived nomination for attorney general and said he will not retake his seat in January, won't be filled until the Spring.
• While Waltz doesn't plan to resign until Jan. 20, Johnson will still be left with a 217-215 majority for some of the key first months of Trump's term.

Between the lines: Governing was enough of a challenge for Republicans during the past two years with a roughly five-seat majority.

• Party-line bills routinely failed on the floor and Republicans struggled to muster the votes for key legislation funding the government, raising the debt ceiling and providing urgent foreign aid to U.S. allies.
• With Trump in the drivers' seat, some Republicans expect that dynamic to only worsen.

Go deeper: Trump is already giving Mike Johnson months of headaches