Republican infighting over spending cuts is risking a government shutdown, the Senate's top Democrats said Thursday.

Democrats seized on negotiations in the House over the level of spending cuts contained within legislation to fund government the rest of this fiscal year to advance their narrative that the GOP is looking to force a shutdown.

"The infighting amongst Republicans is causing gridlock that could risk a government shutdown," Sen. Charles Schumer (D-N.Y.) said in a conference call.

Republicans in the House are engaged in an internal debate over the extend of cuts they'll pursue in their continuing resolution. An initial proposal called for $32 billion in cuts, which fell short of the $100 billion called for in Republicans' campaign document, the "Pledge to America."

GOP leaders had defended the proposal by pointing to the fact that it cut spending to 2008 levels, as they promised, but it didn't placate conservatives, who have demanded Republicans hit that $100 billion figure. Rep. Hal Rodgers (R-Ky.), the chairman of the House Appropriations Committee, said Thursday that the GOP now intended to hit that target.

But while Democrats sewed seeds of discontent, they also all but rejected the kinds of cuts being proposed in the House.

"The House Republican proposal is not responsible," said Senate Majority Leader Harry Reid (D-Nev.). He stopped short of opposing the Republican proposal outright, but said the cuts proposed in the House were poorly-targeted.

"Right now, the different factions of the House Republicans keep trying to outbid each other on spending cuts," Schumer said.