The Nevada Democratic Party has filed its third ethics complaint against Republican Sen. Dean Heller in five months, accusing him of using one of his legislative proposals to fundraise for his re-election effort.

According to a complaint sent Tuesday to the U.S. Senate Select Committee on Ethics, the party is accusing Heller of “soliciting political contributions” through use of a Google search ad that promotes his “No Budget No Pay” proposal, which would prohibit members of Congress from receiving a salary unless they pass a budget and appropriations bills on time every year.

The party claims that using the search ad, which links to a page asking for donations on Heller’s website, violates congressional ethics rules and federal law designed to prevent official resources from being used to promote a political campaign and rules against soliciting contributions for or because of official action.

“This is the self-serving and ethically questionable behavior that Nevadans have come to expect from Sen. Dean Heller,” said Nevada State Democratic Party chair William McCurdy II in a statement. “Heller is so desperate to avoid losing his job in Washington that he’s now willing to break the rules and exploit his taxpayer-funded office in order to try and salvage his political career.”

A spokeswoman for Heller did not respond to a request for comment.

It’s the third complaint the party has filed against Heller, following one in October accusing him of violating election law by sending out a fundraising email touting his position on the Senate Finance Committee and another in January accusing his Senate campaign of inappropriately copy-and-pasting press releases from his Senate office.

The committee, which is composed of three Republicans and three Democrats, hasn’t taken action on the previous complaints filed against Heller.