Former Speaker Newt Gingrich on Wednesday warned House Republicans not to get overly confident about the midterm elections and said the party still needs money to achieve victory in November.

During a closed-door meeting at the Capitol Hill Club, the Georgia Republican said, “Any of you who think this is locked doesn’t get it,” according to GOP sources inside the room. “You have a machine on the other side … trying to take out one candidate at a time.”

Gingrich told lawmakers each of them should give a minimum of $100,000 to close the fundraising gap between the National Republican Congressional Committee and its Democratic counterpart.

“The goal of this conference should be to give as much as possible to the NRCC or individual candidates,” he said.

Gingrich wasn’t the only Republican applying pressure to members to pony up.

Rep. Jeb Hensarling (Texas), a co-chairman of the NRCC’s Battleground program, pointed to a report that Democrats had given $944,000 to the Democratic Congressional Campaign Committee over the past month and urged Republican lawmakers to open their wallets, the GOP sources said. The Battleground program funds the effort to regain seats in the November elections.

Rep. Mike Rogers (R-Mich.), who co-chairs the Battleground effort, said: “Every dollar that you put in will go toward offense. We need to make our commitment. If you’ve got anything extra, give it up. The chairman needs your help.”

House Minority Leader John Boehner used the gathering to explain to his Conference comments he made last weekend about the middle-class tax cuts, House Republican sources said.

The Ohio Republican told “Face the Nation” on Sunday that he would vote for a bill that extended Bush-era tax cuts only individuals making less than $200,000 and for couples making less than $250,000. The remarks caused friction within the GOP ranks, since many Republicans say the cuts should be extended across the board, regardless of income level.

Boehner told Members at the meeting he was “comfortable” with his answer because it deprived the Obama administration and Speaker Nancy Pelosi (D-Calif.) of their argument that Republicans were holding the middle-class tax cuts hostage in order to secure tax cuts for the wealthy.

He added that a “bipartisan majority” wanted to include the tax cuts for couples making $250,000 or more.

Republican leaders at a press conference Wednesday reaffirmed their commitment to extend the Bush tax cuts for all Americans.

“The American people want to stop all the tax hikes, and Republicans are going to continue to stand with them,” Boehner said. “Raising taxes on anyone, especially small businesses, is the exact wrong thing to do in a struggling economy.”

Anna Palmer contributed to this report.