Topeka ? Democrat Paul Davis pushed back against Republican claims Thursday that he wouldn’t contest any Washington policies, saying he would vigorously fight a new federal rule that asserts authority over many of the nation’s streams and wetlands if he’s elected Kansas governor.

Davis made the assertion just minutes after Republican Gov. Sam Brownback announced his own protest against the new law and suggested his Democratic challenger wouldn’t do the same.

Kansas agriculture and energy groups are upset about the U.S. Environmental Protection Agency’s proposal to clarify which waters are shielded under federal law from development. The groups view the proposed change as a federal overreach, and state officials believe it would increase the number of stream miles under federal jurisdiction in Kansas from 34,000 to 174,000.

Both candidates have jumped on the issue as they try to woo rural voters in their tight race in the GOP-leaning state.

The governor moved first, saying during a news conference Thursday that his administration was sending a letter to the EPA asking it to withdraw the proposed rule.

“We’ve fought consistently against the federal control in this area, and we’re going to continue to do that,” said Brownback, who is seeking his second term in office. The governor also said Davis “hasn’t pushed back on anything” proposed by President Barack Obama.

Davis said at his own news conference less than an hour later: “I certainly will do more than send a letter.” He said he would consider suing the federal government if it didn’t back off the rule.

“I think we’ll look at all of the options that are on the table in order to protect the interests of Kansas,” Davis said.

Davis has criticized Brownback for being overly combative toward the Democratic president’s administration. On Thursday, Davis said he would “proactively engage” the federal government to get results instead of resorting to “political rhetoric.”

Brownback has for months criticized the proposed EPA rule, calling it an attempt by the Obama administration to impose overly burdensome regulations on business.

The governor and his allies also have repeatedly noted that Davis, a Kansas House member, was an Obama delegate to the 2008 and 2012 Democratic National Conventions. Obama received only 38 percent of the vote in Kansas in winning re-election two years ago.

EPA Administrator Gina McCarthy has said the rule isn’t designed to hamper agriculture, but to protect downstream water quality for all Americans. The rule is a response to U.S. Supreme Court decisions in 2001 and 2006, that limited federal regulators’ reach but weren’t clear about their authority over small waterways.

Brownback contends that under the rule, land owners and businesses could face restrictions and costly permits for routine activities such as farmers’ applying pesticides on their land. Davis said the proposed rule “would be very damaging for Kansas.”