AUGUSTA — The Maine Senate today defeated a request by a Democratic lawmaker that would have required new rules to be written for constitutional officers who run for higher office.

Sen. John Patrick, D-Rumford, said he believes there’s a “perception problem” in the public now that all three of the state’s constitutional officers are running for the U.S. Senate seat that will be open because of the retirement of Sen. Olympia Snowe.

Attorney General William Schneider, Treasurer Bruce Poliquin and Secretary of State Charlie Summers are all seeking the Republican nomination for the seat. In Maine, constitutional officers are appointed by the majority party in the Legislature.

“It’s not illegal, but there is a perception problem,” Patrick said during Senate debate. “Constitutional officers should be apolitical.”

Last week, Schneider, Poliquin and Summers told the Portland Press Herald that they are taking steps to ensure that their day jobs don’t interfere with their campaigns. Summers said he has asked his deputy, Julie Flynn, to oversee elections. All three said they would use vacation time, evenings and weekends to run their campaigns.

During today’s Senate debate, Republicans pointed out that several Democrats who served as constitutional officers in the past have run for higher office.

“I don’t recall a single display of raw partisanship on the floor of the Senate in response to their candidacies,” said Senate President Kevin Raye, R-Perry.

Patrick’s request for a bill to set guidelines for constitutional officers who are running for higher office was rejected last week by legislative leaders. Today, he put forward a joint order to the entire Senate, which was defeated 21-12.

Sen. Bill Diamond, D-Windham, who ran for Congress while serving as Secretary of State, said it would be a good idea to set guidelines. But, he said the issue can wait until next year, when a new Legislature is seated.

“To do it now doesn’t strike me as fair,” he said.

Sen. Richard Woodbury, a Yarmouth independent, said he too would welcome consideration of rules for constitutional officers. But he voted to reject the request to do it this year.

“The timing to me feels just a little too politically motivated,” he said.

In addition to Summers, Poliquin and Schneider, former Senate President Rick Bennett, state Sen. Debra Plowman, and businessman Scott D’Amboise are seeking the Republican nomination.

On the Democratic side, state Sen. Cynthia Dill, state Rep. Jon Hinck and former Secretary of State Matt Dunlap are working to get their party’s nomination.

Former Governor Angus King, an independent, has also declared his intention to run.