Maine state House Speaker Sara Gideon, a Democrat, is currently leading Republican Sen. Susan Collins by four points, according to a poll released Monday from Public Policy Polling (PPP). The survey shows Gideon with 46% of the vote to Collins’ 42%.

The election is expected to be among the closely watched, as Collins is considered among the most vulnerable incumbents.

Collins, 67, has been in the Senate since 1996 and had been viewed by many as a “moderate Republican.” She holds pro-choice views, breaking with much of her party, and also supports same-sex marriage. She has promoted her more centrist stances as a way to gain support from Maine’s liberal coast, along with the more conservative interior of the state. She won her last race in 2014 by 37 points against Democratic challenger Shenna Bellows.

However, Collins has lost support from liberals in her state, mainly due to her votes on Brett Kavanaugh’s Supreme Court confirmation and the Trump impeachment trial.

Collins voted to confirm Kavanaugh, who had the most conservative or second-most conservative voting record on the D.C. Circuit, and despite allegations he sexually assaulted Christine Blasey Ford while they were both in high school. During the trial, Collins voted to acquit Trump on both charges: abuse of power and obstruction of Congress. Trump had been accused of withholding military aid to coerce Ukraine into conducting an investigation for his political interests.

Collins has among the worst approval ratings of any senator. According to the PPP survey, only 36% of respondents approve of Collins’ job performance, with 55% disapproving. The poll also shows 51% of respondents believe that Trump should have been impeached and removed, with 44% against that idea.

Gideon, who has served as Maine’s state House speaker since 2016, has slammed Collins’ decisions on Kavanaugh and the impeachment trial. Gideon will have to win the July 14 Democratic primary against lobbyist and businesswoman Betsy Sweet and attorney Bre Kidman. Polls show Gideon with a commanding lead in the primary.

Presumptive Democratic presidential nominee Joe Biden is expected to win Maine in the general election. The PPP survey shows Biden at 53% support in the state, with Trump at 42%. The last time a Democratic nominee failed to win Maine was in 1988.

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