WASHINGTON — Two senior Republicans said Sunday that they might be open to raising new government revenue as part of a deal to resolve the dispute over the federal debt ceiling, but they warned that there was little time to enact a comprehensive deal.

One of the senators, John Cornyn of Texas, said he would consider eliminating some tax breaks and corporate subsidies in the context of changes in the tax code, provided there was not an overall increase in taxes.

“I think it’s clear that the Republicans are opposed to any tax hikes, particularly during a fragile economic recovery,” Mr. Cornyn said on “Fox News Sunday.” “Now, do we believe tax reform is necessary? I would say absolutely.”

But he insisted that any changes in taxes be “revenue neutral,” meaning that the government would not take in any more money from individuals or businesses than it does now.