Supreme Court Justice nominee Judge Neil Gorsuch testifies March 21, 2017, on Capitol Hill in Washington during his confirmation hearing before the Senate Judiciary Committee.

Both of Maine’s senators have big decisions to make this week as Republicans prepare to install Neil Gorsuch into a long-vacant U.S. Supreme Court seat.

For independent Angus King, the first step is deciding whether or not he’ll endorse Gorsuch. So far, he’s remained on the fence.

The state’s senior senator, Republican Susan Collins, strongly backs Gorsuch for the court but it’s not yet clear whether she’ll vote to end the filibuster rule for Supreme Court nominations that stands in the way of his confirmation.

April Humphrey of Yarmouth, a co-founder of the grass-roots Mainers for Accountable Leadership said Monday that the struggle to block Gorsuch “has me absolutely sick” because she views the Colorado judge as an extremist.

Hoping to sway King, the group collected signatures from 96 lawyers around Maine drafted by Jackie Sartoris, an attorney in Brunswick.

“Gorsuch would shape our jurisprudence for generations and his opinions show that he is not a normal candidate, but an activist judge with an extreme agenda,” she said in a prepared statement.

Humphrey said she hopes the letter appeals to King’s thoughtfulness and convinces him to join the Democrats who are largely aligned against Gorsuch.

“This is going to be a litmus test for progressives,” she said.

Humphrey said they’re also keeping a close eye on Collins, who has defended Senate rules for years but may be willing to join the GOP in getting rid of filibusters for Supreme Court justices in order to push Gorsuch over the finish line this week. Democrats threw out filibusters for other judicial nominations the last time they controlled the Senate.

“We’re really hoping that she’ll oppose the nuclear option,” Humphrey said.

There are enough Democrats on record as saying they won’t vote to close off debate to prevent the nomination of Gorsuch from coming to a vote unless the Republicans change the rules, something that GOP leaders have said they’ll do if they must.