In the intensifying debate over a proposed health insurance merger, Connecticut Gov. Dannel Malloy is doing the seemingly impossible: bringing together powerful voices from both parties. But the problem for Malloy is that those forces are unifying against him — just as he prepares for a high-profile role at the Democratic National Convention and his administration deals with a merger-related ethics probe.

As Connecticut leads the multistate review of Anthem’s proposed merger with Cigna, the national group Democracy for America — which grew out of Howard Dean’s presidential campaign — submitted a 20,000-signature petition to Democratic officials earlier this month demanding that Gov. Malloy either use his power to block the merger, or step down from his role overseeing the DNC’s rules committee. Now, Connecticut Republican lawmakers are making a similar demand: In a press release blasted out Wednesday, they slammed Malloy for appointing a former Cigna lobbyist to oversee the merger review, and said the governor must use his power to stop the transaction.

“There is a dark cloud of doubt engulfing the entire merger process,” said Connecticut Senate Minority Leader Len Fasano and two other senior Republican lawmakers, citing International Business Times’ investigative series on the merger. “First, you have a commissioner overseeing the merger who has direct ties to one of the insurance companies and who has refused to recuse herself or recognize any conflict of interest. Then, you have that same commissioner being less than forthcoming with information requested of her department, thereby casting a shadow on any claim to transparency. Finally, you have two insurance companies that have upped their political donations significantly in recent months, coinciding with their efforts to gain state support for their merger around the country. This whole situation casts a shadow of distrust on the process.”

They concluded: “At this point, denying the merger is the only way to lift that cloud.”

While other statewide elected Democrats in Connecticut such as U.S. Senator Richard Blumenthal and Attorney General George Jepsen have recently expressed concern about the merger, Malloy’s office declined to comment on the calls for him to take a public position on the deal.  In the past, Malloy has said his administration’s choice about whether to block or approve the merger is “an independent decision” being made by his Insurance Department — the one run by his appointee, former Cigna lobbyist Katharine Wade.

The Republicans’ demand comes hours after reports that the Department of Justice is preparing to file a lawsuit to block the merger. It also comes on the final day that the public can submit comments to the Connecticut Office of State Ethics in its investigation into whether Wade’s ties to Cigna constitute an impermissible conflict of interest.

The Republican lawmakers pressuring Malloy filed their comments to the Ethics Office on Wednesday. The ethics office is scheduled to meet on Thursday and vote on setting a concrete date for issuing a formal ruling.

Updated at 3:35pm ET