Nicola Sturgeon, Scotland's first minister and leader of the Scottish National Party, speaks during a news conference at Bute House in Edinburgh on June 9. (Russell Cheyne/AFP/Getty Images)

The British election results announced Friday were a severe setback for Prime Minister Theresa May and her plans for tough Brexit negotiations. But there may have been another casualty from the vote: Scotland’s bid for independence.

The pro-independence Scottish National Party (SNP), led by Nicola Sturgeon, lost about a third of its parliamentary seats in the general election. The party will now have 35 seats, compared with the 56 it held before.

Sturgeon, who also leads the Scottish government, had repeatedly called for a new vote on independence. Scottish voters had rejected such a move in a 2014 referendum.

Following the setback in Thursday’s election, Sturgeon acknowledged that she was “disappointed” but did not completely rule out pursuing a second referendum. She said she would not make “rash decisions.”

But her opponents say she will have no choice but to drop the demand for a new vote, at least for the foreseeable future. 

Sturgeon’s party scored a landslide victory in Scotland in the 2015 general election, taking 56 of 59 seats. Many of the votes her party lost on Thursday went to the Scottish Conservatives, the Labour Party and the Liberal Democrats, all of whom have indicated an unwillingness to support another referendum. 

One of the SNP politicians who lost his seat to the Conservatives was Alex Salmond, who served as Scotland’s first minister — or government leader — until 2014 and led the pro-
independence party for more than 20 years. His defeat was seen as an indication of how much support the SNP had lost in some of its core strongholds. 

Speaking of a “historic night,” the leader of the Scottish Conservative and Unionist Party, Ruth Davidson, told the BBC that plans for a second independence vote were now “dead.”

“That’s what we have seen tonight,” she said. 

“We had a very clear message in this campaign, and there wouldn’t have been so many SNP losses tonight if Nicola Sturgeon hadn’t tried to force through an unwanted second independence referendum,” said Davidson.

While the Conservative Party suffered losses in much of Britain, its Scottish branch led by Davidson had its best result in more than three decades. 

Despite attempts by parts of the SNP not to frame the general election as a de facto vote on a second independence referendum, many Scots perceived it to be the defining issue of the campaign. 

The SNP’s last attempt to separate Scotland from the United Kingdom failed by 10 points. Although pro-independence activists celebrated the party’s ­sudden rise at the time, there was also a sentiment that Scotland’s nationalists had just missed a once-in-a-lifetime opportunity. 

Both May’s decision to announce snap elections two months ago and Sturgeon’s demand last summer for a second referendum were driven by the hope that Brexit would realign the political landscape in their favor. Scotland had voted overwhelmingly against withdrawal from the European Union, so Sturgeon believed voter support for independence would increase.

But both May and Sturgeon appear to have miscalculated their odds of winning. 

May likely overestimated Britons’ support for her plans to make a sharp break from the E.U., a move that would leave few of its membership privileges intact. Sturgeon likely over­estimated voters’ desire to break away from Britain. Polls show around 40 percent of voters in Scotland back independence.

Preserving Scotland’s E.U. membership has been the key driving force in her campaign for a new independence vote. Much had changed since the last referendum in 2014, when British government officials helped to persuade Scottish voters to remain part of the United Kingdom by promising them that it was the only way to stay in the E.U.

At the time, a referendum on Britain leaving the E.U. still seemed unthinkable. In the Brexit referendum, Scots voted to remain part of the E.U. by a margin of 24 percentage points.