Washington CNN  — 

An energized Democratic base is translating into a clear fundraising advantage for the party’s House candidates in this year’s midterm elections.

The latest sign came in Federal Election Commission data filed last week showing that Democratic challengers outraised Republican incumbents in more than two dozen contests that made CNN’s Key Races list.

The breakdown: six Republican seats currently rated as Toss-Ups, eight ranked as Lean Republican and 11 Likely Republican races.

One seat that stands out: New York’s 22nd Congressional District, where 39-year-old Assemblyman Anthony Brindisi not only raised nearly $100,000 more than GOP Rep. Claudia Tenney, he also closed the year with roughly $18,000 more cash on hand. That seat moves from Lean Republican to Toss-Up.

The money momentum has also helped fuel Democrats who are seeking re-election in potentially tough districts. California’s Rep. Ami Bera is no stranger to tight races, winning re-election last year by just 2 points. But he has nearly $1 million more in the bank than Republican Andrew Grant – an edge that shifts his race from Lean to Likely Democratic.

Several other Democrats fell off the list entirely, moving from Likely Democratic ratings to safe territory, after strong fundraising quarters – and weak showings by their Republican foes. In Iowa’s 2nd District, Rep. Dave Loebsack has more than $1.6 million in the bank, outpacing Republican Christopher Peters, who had less than $13,000. Reps. Tom Suozzi in New York’s 3rd District and Salud Carbajal in California’s 24th District are also running about $1 million ahead of their challengers.

Those sluggish performances by Republican challengers underscore a reality of the House battleground map this year: With the exception of a handful of seats, including two in Minnesota, the GOP is almost entirely on defense – pouring money and energy into saving enough incumbents to protect what’s now a 24-seat House majority

An addition to the list is Arkansas’ 2nd District, where Republican Rep. French Hill moves from safe territory to a Likely Republican rating now that state Rep. Clarke Tucker has entered the race. It’s a district President Donald Trump won by 11 points in 2016, but given Democrats’ recent wins in statewide races in Virginia and Alabama and state legislative special elections in Trump-won districts in Wisconsin and Missouri, it’s worth watching.