Democrats on Sunday defended their party’s tit-for-tat threats to match the partisan Congressional redistricting effort Republicans are pursuing in Texas.

Proposals to draw new maps that have been floated in Democrat-led states like New York and California are a last resort, some party leaders said Sunday. But as the Texas drama grinds on, with Republicans threatening to arrest or oust from office Democratic state legislators who fled the state to stall a vote on an unusual mid-decade Republican redistricting plan, some Democrats said they were prepared to use any tool at their disposal.

Sen. Bernie Sanders, Independent of Vermont, said that Democrats, with whom he caucuses, have little choice but to respond in kind to the Republicans’ plan, which is designed to flip five U.S. House seats into the Republican column.

“What should Democrats do? Sit back and say, ‘Oh, gee?’” Mr. Sanders said on CNN. “Let them win the election when they shouldn’t? So Democrats have got to fight back.”

Mr. Sanders has long opposed partisan gerrymandering. But he told CNN’s Dana Bash that the effort in Texas amounted to an attempt to “rig the system” and keep Republicans in power despite an unpopular legislative agenda. The tools at Democrats’ disposal are limited, and to preserve even the chance of victory in next year’s midterms, Mr. Sanders said, Democratic governors are left with but one unsavory option.

“I think it’s pathetic, but I think that’s what they’ve got to do,” he said.

Eric H. Holder, Jr., the chairman of the National Democratic Redistricting Committee and former attorney general, said on NBC that “there’s no question that gerrymandering is a threat to our democracy.” But he, too, endorsed Democrats’ plans to counter Texas’ maps in a manner that “is responsive and is temporary.”