Senator Mitch McConnell celebrates with his wife, Elaine Chao, on election night. Photograph by Aaron P. Bernstein / Getty

Last week, just days before the election that would elevate the Kentucky Republican Mitch McConnell to Majority Leader of the Senate, his campaign glimpsed potential disaster. In a Fox News interview, McConnell mentioned arithmetic, noting that repealing Obamacare would require sixty votes in the Senate and Presidential approval. That was a grave political blunder, because it led some conservatives to suspect that he did not intend to dedicate the Senate’s time to a fruitless symbolic pageant of protest. The Senate Conservatives Fund, which backs Tea Party candidates, declared, “Mitch McConnell Surrenders on Obamacare Repeal.”

Given that McConnell had vowed to pull out Obamacare “root and branch,” his description of Senate mechanics was received as apostasy. “This is why nobody believes Mitch McConnell anymore," Mary Vought, a spokeswoman for the Senate Conservatives Fund, told NPR. The Senator’s campaign quickly clarified: “Leader McConnell is and has always been committed to the full repeal of Obamacare,” Brian McGuire, his spokesman, said. “He knows it won’t be easy, but he also believes that if Republicans are fortunate enough to take back the majority, we’ll owe it to the American people to try.” Before midnight on Tuesday, McConnell had retained his seat, beating Alison Lundergan Grimes, the Democrat, by sixteen points, and the G.O.P. had taken back the Senate with a string of victories.

For months, as McConnell fended off Lundergan Grimes, a thirty-five-year-old relative newcomer, he largely avoided spelling out the details of what he envisions in the event that his party takes control of the Senate for the first time since 2006. But as his lead widened, and as the G.O.P. looked increasingly likely to gain the six seats it needed, the age of McConnell came more fully into view. One feature is clear: having gained the top job, a position he has coveted for decades, McConnell will find himself less a leader than a captive.

There are two ways this scenario can play out—one dark, one rosy. The rosy scenario begins with the true, if glib-sounding, observation that the Senate is already in a state of gridlock with the Democrats in control of both it and the White House. Perhaps now, with Republicans no longer only an opposition party, both sides will see an incentive to deal. McConnell, the theory goes, will understand that he has as little as two years to make his mark as leader, opposite a President in the same predicament. Make no mistake: this is not likely to produce major legislation from the Democrats’ agenda—a higher minimum wage, equal pay for women, affordable college tuition—but it could raise the faint spectre of compromise over lower-hanging goals such as a tax overhaul, trade promotion, or investment in roads and bridges.

Unfortunately, my money is on the darker scenario, which holds that we are entering a period of paralysis that will be the functional equivalent of turning down the radiators and draining the pipes in the Capitol until the 2016 election. McConnell has told big donors that he will “work at every turn to thwart the Obama agenda, and use appropriations and the budget process to force the president to roll back key elements of Obamacare, to water down Dodd-Frank, to tilt toward coal … to move forward on the Keystone XL pipeline, and to stop Environmental Protection Agency action on climate change,” according to the National Journal.

For some Republican senators, that will not be enough. Before the election, Senator Ted Cruz, of Texas, refused to pledge his support to McConnell, and offered his own vision of the Senate’s priorities, including opening congressional hearings into the actions of the Obama Administration, “looking at the abuse of power, the executive abuse, the regulatory abuse, the lawlessness that sadly has pervaded this administration.” In addition to the power to investigate, the tools available to the majority party include committee chairmanships (which largely determine what kinds of witnesses get to testify at, for instance, hearings on climate change) and control in shaping the federal bench (including, perhaps, the Supreme Court).

Moreover, Cruz might look like a moderate next to some of his new colleagues; in Iowa, the Republican Joni Ernst, as the Times summed it up, “wants to ban abortions and same-sex marriage and impeach the president.” It is a measure of our moment that McConnell was greeted as a peacemaker when he told reporters that he would not rank investigating the President as his top priority: “Obviously, we intend to be a responsible governing Republican majority, if the American people give us the chance to do that,” he said. In other venues, he has explained that this means he will attach partisan requirements to routine spending bills—removing, say, standards for clean water, or efforts to reduce carbon emissions—in order to force the President to choose between accepting Republican policies and seeing parts of the government shut down.

There is yet another force that constrains McConnell, and drives him to the right. The Senate map in 2016 is not good for his party; seven incumbents will be facing reëlection in states that sided with Obama in both elections, and two others are in states where Obama prevailed once. McConnell will do his best to give the Republicans an advantage, which likely means fighting against any remaining restrictions on money in politics. The spending in his own race against Grimes added up to an estimated eighty million dollars, but McConnell, who was a plaintiff in the case that resulted in the Supreme Court’s Citizens United decision, believes there is too little money in politics. Some years ago, U.S. News ran a headline calling him the Darth Vader of campaign finance, and he hung it on his office wall.

McConnell, for his part, has greeted the prospect of his ascension with muted satisfaction. He is, to begin with, a person of sedate physical expression, but one also senses that he knows the predicament that awaits him. In the final days of his campaign, he travelled Kentucky with “Team Mitch” stencilled over his heart, and “Eye of the Tiger” on the loudspeaker. His own message was uncomplicated; Molly Ball, of The Atlantic, snapped a picture of a McConnell bumper sticker of elegant brevity: “COAL. GUNS. FREEDOM.” (It’s hard to think of a counter-sticker with the same zing: “WIND. KALE. GOVERNANCE.”) Grimes never achieved the inroads she would have needed to win in Coal Country, or the lead she might have expected among women and younger voters.

In so many ways, McConnell is the leader that this U.S. Senate deserves. He is a pure political being: he entered politics as a center-leaning, pro-environment, pro-choice Republican in a Democratic state; year by year, he has marched to the right in step with his Party, cycling through positions on collective bargaining and minimum wage. If McConnell has a deep instinct to rise above it all now, in a bid for comity and history, he hides it well. He privileges the scoreboard above all. Asked about his ideological evolution, he explained simply, “I wanted to win.”

Read more analysis and commentary at our 2014 midterms hub.