Senate Democrats beg Sen. Susan Collins (R-ME) not to run for governor of Maine, a move that would rid the Senate of one of its most liberal Republicans.

When Sen. Heidi Heitkamp (D-ND) heard that Sen. Collins might run for Maine governor in 2018, Heitkamp texted Collins, “Don’t do it.” Heitkamp added, “I desperately hope she doesn’t run.”

Collins’ departure would serve as another blow to moderates and centrists in the upper chamber of Congress. She was an infamous roadblock against repealing Obamacare this year; Collins’ vote against the “skinny” Obamacare repeal bill and opposition to the Graham-Cassidy block grant legislation tanked Obamacare repeal twice.

Collins’ opposition to Obamacare repeal drew the ire of Maine Republican Gov. Paul LePage, who endorsed the Graham-Cassidy legislation. During the Graham-Cassidy debate, Gov. LePage called on Collins to “start paying attention to Maine people.”

Most Republicans remain quiet about whether Collins should stay in the Senate or run for governor, although Senate Democrats and independents continue to urge her to stay in Congress.

Sen. Angus King (I-ME), who caucuses with Democrats, reportedly urged her to remain in the Senate also.

Sen. Claire McCaskill (D-MO), too, called on her to stay in the Senate. McCaskill claimed, “She’s so important to the country here. We don’t have enough folks like her.”

Sen. Collins faces an uphill battle if she runs for governor of Maine. A survey indicated that Collins has become increasingly unpopular among Maine Republican primary voters. Sixty-two percent of Maine citizens disapproved of her job performance, and 62 percent of those polled also said they would rather vote for someone else in the Republican primary for Maine governor. Forty-four percent of Maine Republicans polled suggested they would rather support Mary Mayhew, the former Health and Human Services commissioner for Maine. Sixty-one percent of Maine Republican primary voters suggested that Sen. Collins’ voting against Obamacare repeal made them less likely to vote for Collins for governor.

Given that Collins voted against Obamacare repeal in 2015, voted against the “skinny” repeal in July, and opposed the Graham-Cassidy Obamacare repeal bill this fall, some conservatives have questioned whether she represents Maine in the Senate as a Republican in name only.

Jason Pye, vice president of legislative affairs for FreedomWorks, asked, “Is Susan Collins actually a Republican? She conferences with the Republicans, there’s an R next to her name, but a question mark is more appropriate.”