The partisan fight over the late Antonin Scalia’s Court seat may hand the Democrats a significant advantage in the 2016 election. Photograph by Haraz N. Ghanbari / AP

Around 4:30 P.M. Eastern time on Saturday, the San Antonio Express-News broke the news of the death of Antonin Scalia, the conservative Supreme Court Justice. Within a few hours, the Republican Party had placed itself on a trajectory that, if isn’t reversed, could throw the Presidential election to the Democrats.

In apparent contravention of precedent and the U.S. Constitution, the leader of the Republican majority in the U.S. Senate, Mitch McConnell, said that President Obama shouldn’t be allowed to name a replacement for Scalia. “The American people should have a voice in the selection of their next Supreme Court Justice,” McConnell said in a statement posted on his Facebook page. “Therefore, this vacancy should not be filled until we have a new President.”

At least three of the Republican Presidential candidates—Ted Cruz, Marco Rubio, and Ben Carson—also called for the replacement of Scalia to be delayed until after the election. Apparently oblivious to the outrage such a suggestion would prompt among Democrats and independent-minded Americans who dislike partisan warfare, Carson said, “It is imperative that the Senate not allow President Obama to diminish Justice Scalia’s legacy by trying to nominate an individual who would carry on his wishes to subvert the will of the people.”

Others better qualified than me can discuss the constitutional implications of such statements. But, in political terms, the party appears to be intent on hurtling into a deep pit. It is well known, and accepted on both sides, that the Democrats’ hopes of holding on to the White House hinge on getting a high voter turnout on November 8th. If you were a Democratic strategist trying to maximize turnout, what would you most like to see? One possibility, surely, is the prospect of the election being transformed into a referendum on the President versus the do-nothing Republican Congress.

Could this really happen? The President has already said that the White House will nominate someone to replace Scalia. Similarly, there is little doubt that the Republicans will block the nomination. “What is less than zero? The chances of Obama successfully appointing a Supreme Court Justice to replace Scalia?” Conn Carroll, the communications director for Republican Senator Mike Lee, a member of the Judiciary Committee, asked in a tweet.

If the Republicans block the nomination without properly considering it, which also seems likely, a huge political row will ensue, enveloping the Presidential race. (In fact, it has already done that, as the Republican debate proved.) Come summer and fall, the Democratic candidate, be it Hillary Clinton or Bernie Sanders, will be able to go the country and appeal for support in preventing the Republicans from humiliating President Obama and making a mockery of democracy.

Small wonder, some senior Democrats already appear to be dancing a jig. “President Obama is President until January 20, 2017—that is a fact, whether the Republicans like it or not,” Hillary Clinton said. “Well, the Senate GOP might just have ensured the Obama coalition turns out in 16,” David Plouffe, a former senior adviser to the President, tweeted on Saturday evening. “Dem WH for 16 straight years, Dem Senate in ’17. Geniuses.” David Axelrod, a current Obama adviser, was a bit more measured, tweeting, “Senate roadblock to any Scalia replacement could be burdensome issue for @GOP in fall. But base would erupt if Obama nominee confirmed.”

Axelrod’s last point is well taken. But the speed with which Republicans embarked on their course didn’t appear to reflect a measured accounting of the pluses and minuses. It looked like high-stakes politics being played out in Internet time.

At 5:27 P.M., about an hour after news of Scalia’s death first broke, Cruz tweeted, “Justice Scalia was an American hero. We owe it to him, & the Nation, for the Senate to ensure that the next President names his replacement.” When I saw Cruz’s tweet, which was quickly retweeted hundreds of times, I assumed that he was trying to get out ahead of his rivals in the G.O.P. primaries, who were due to debate with him just a few hours later, in South Carolina. And, by Cruz’s lights, he initially appeared to have succeeded. At about the same time the Texas senator sent out his incendiary tweet, Donald Trump, the Republican frontrunner, tweeted out a message describing Scalia’s death as “a massive setback for the Conservative movement and our COUNTRY!,” but, at least at first, he didn’t say anything about preventing President Obama from naming a replacement. John Kasich, the Governor of Ohio, also released a respectful statement about Scalia that didn’t mention replacement. Jeb Bush did likewise, saying that he had prayed for Scalia, a fellow Roman Catholic, at mass.

But Cruz wasn’t out by himself for long—just half an hour, in fact. Shortly after 6 P.M., Senator Marco Rubio released a statement in which he hailed Scalia as “one of the most consequential Americans in our history,” and added, “The _next”—_my emphasis added—president must nominate a justice who will continue Justice Scalia’s unwavering belief in the founding principles that we hold dear.”

By 7 P.M. or thereabouts, Carson and McConnell had also jumped aboard the campaign to block Obama’s nominee at all costs. And as the G.O.P. debate unfolded a few hours later, Jeb Bush was the only candidate who seemed willing to reconsider the course the Party was embarking on. Cruz and Rubio stuck to what they had said earlier. Trump said that McConnell and other Senate Republicans should “delay, delay, delay.” Kasich added that “the President should not move forward” with nominating a replacement for Scalia. But Bush, though he expressed doubt that the White House would nominate a “consensus pick,” also said that the President “has every right to nominate Supreme Court Justices,” adding, “I’m an Article II guy.” Evidently, that leaves the former Florida governor in a small minority.