Actions under presidential administrations since 2009
As the leading Republican senator, McConnell confronted and pressured other Republican senators who were willing to negotiate with Democrats and the Obama administration. According to Purdue University political scientist Bert A. Rockman, "pure party line voting has been evident now for some time ... but rarely has the tactic of 'oppositionism' been so boldly stated as McConnell did." According to University of Texas legal scholar Sanford Levinson, McConnell learned that obstruction and Republican unity were the optimal ways to ensure Republican gains in upcoming elections after he observed how Democratic cooperation with the Bush administration on No Child Left Behind and Medicare Part D helped Bush's 2004 reelection. Levinson noted, "McConnell altogether rationally ... concluded that Republicans have nothing to gain, as a political party, from collaborating in anything that the president could then claim as an achievement." A number of political scientists, historians, and legal scholars have characterized McConnell's obstructionism and constitutional hardball as contributors to democratic erosion in the United States.
In October 2010, McConnell said, "the single most important thing we want to achieve is for President Obama to be a one-term president." Asked whether this meant "endless, or at least frequent, confrontation with the president", McConnell said, "if [Obama is] willing to meet us halfway on some of the biggest issues, it's not inappropriate for us to do business with him." According to political scientists Jacob Hacker and Paul Pierson, "Facing off against Obama, [McConnell] worked to deny even minimal Republican support for major presidential initiatives—initiatives that were, as a rule, in keeping with the moderate model of decades past, and often with moderate Republican stances of a few years past." The New York Times wrote early in Obama's administration that "on the major issues—not just health care, but financial regulation and the economic stimulus package, among others—Mr. McConnell has held Republican defections to somewhere between minimal and nonexistent, allowing him to slow the Democratic agenda if not defeat aspects of it." The Republican caucus threatened repeatedly to force the United States to default on its debt, McConnell saying he had learned from the 2011 debt-ceiling crisis that "it's a hostage that's worth ransoming".
McConnell worked to delay and obstruct health care reform and banking reform, two of the most notable pieces of legislation that Democrats navigated through Congress early in Obama's tenure. Political scientists noted that "by slowing action even on measures supported by many Republicans, McConnell capitalized on the scarcity of floor time, forcing Democratic leaders into difficult trade-offs concerning which measures were worth pursuing. ... Slowing the Senate's ability to process even routine measures limited the sheer volume of liberal bills that could be adopted."
McConnell initially endorsed fellow Kentucky senator Rand Paul for president in 2016. Paul withdrew from the race after the Iowa caucuses, and McConnell endorsed presumptive nominee Donald Trump on May 4, 2016. But McConnell disagreed with Trump on many occasions. In May 2016, after Trump suggested that federal judge Gonzalo P. Curiel was biased against Trump because of his Mexican heritage, McConnell said: "I don't agree with what [Trump] had to say. This is a man who was born in Indiana. All of us came here from somewhere else." In July 2016, after Trump criticized the parents of Humayun Khan, a Muslim-American soldier who was killed in Iraq, McConnell said, "All Americans should value the patriotic service of the patriots who volunteer to selflessly defend us in the armed services." On October 7, 2016, following the Donald Trump Access Hollywood controversy, McConnell said, "As the father of three daughters, I strongly believe that Trump needs to apologize directly to women and girls everywhere, and take full responsibility for the utter lack of respect for women shown in his comments on that tape." In private, McConnell reportedly expresses disdain for Trump and "abhors" his behavior.
In October 2017, White House chief strategist Steve Bannon and other Trump allies blamed McConnell for stalling the Trump administration's legislation. In response, McConnell cited Neil Gorsuch's confirmation to the Supreme Court to show that the Senate supported Trump's agenda.
After Joe Biden defeated Trump in the 2020 election, McConnell at first refused to recognize Biden as the winner. In his public statements, McConnell did not repeat any of Trump's false claims of voter fraud, but did not contradict them, ignoring questions about evidence and instead arguing that Trump had the right to challenge the results. At the same time that McConnell refused to recognize Biden, he celebrated Republicans who won their Senate and House races in the same elections.
On December 15, the day after the electoral college vote, McConnell reversed his stance and publicly acknowledged Biden's win, saying, "Today, I want to congratulate President-elect Joe Biden." On January 6, during the Electoral College vote count, McConnell spoke out against the efforts of Trump and his allies to overturn the election:
Trump claims the election was stolen. The assertions range from specific local allegations to constitutional arguments to sweeping conspiracy theories ... nothing before us proves illegality anywhere near the massive scale—the massive scale—that would have tipped the entire election. ... If this election were overturned by mere allegations from the losing side, our democracy would enter a death spiral. We'd never see the whole nation accept an election again. Every four years would be a scramble for power at any cost.
Later that day, he described the storming of the Capitol building (which occurred while the Electoral College votes were being counted) as a "failed insurrection" that "tried to disrupt our democracy".
On April 10, 2021, Trump called McConnell a "dumb son of a bitch". Trump added: "I hired his wife. Did he ever say thank you?" Trump has continued to attack McConnell in personal terms since then, but McConnell has not responded publicly.
On November 5, 2019, as the House of Representatives began public hearings on the impeachment of President Trump, McConnell said, "I'm pretty sure how [an impeachment trial is] likely to end. ... If it were today, I don't think there's any question. It would not lead to a removal."
On December 14, 2019, McConnell met with White House counsel Pat Cipollone and White House legislative affairs director Eric Ueland. Later that day, he said that for Trump's impeachment trial, he would be in "total coordination with the White House counsel's office" and Trump's representatives. He also said there was "no chance" the Senate would convict Trump and remove him from office.
On December 17, 2019, McConnell rejected a request to call four witnesses for Trump's impeachment trial because, according to McConnell, the Senate's role was to "act as judge and jury", not to investigate. Later that day, McConnell told the media: "I'm not an impartial juror [in this impeachment trial]. This is a political process. There's not anything judicial about it."
After Trump's acquittal, McConnell was noted for his ability to block witnesses, to secure Trump's acquittal, and to maintain party unity during the impeachment process. Commentators noted that he had kept Republican senators "marching in lockstep" throughout the process.
On January 12, 2021, it was reported that McConnell supported impeaching Trump for his role in inciting the 2021 storming of the United States Capitol, believing it would make it easier for Republicans to purge the party of Trump and rebuild the party. On January 13, despite having the authority to call for an emergency meeting of the Senate to hold the Senate trial, McConnell did not do so, claiming unanimous consent was required. He called for delaying the Senate trial until after Biden's inauguration. In the Senate trial, McConnell voted to acquit Trump on February 13, 2021, saying it was unconstitutional to convict a president who was no longer in office.
The vote to convict was a bipartisan majority (57–43) but not enough to pass the two-thirds threshold. After the vote, McConnell lambasted and condemned Trump in a 20-minute speech on the Senate floor, saying he believed Trump was guilty of everything the House managers alleged. He said:
Former President Trump's actions preceding the riot were a disgraceful dereliction of duty ... There is no question that President Trump is practically and morally responsible for provoking the events of that day ... If President Trump were still in office, I would have carefully considered whether the House managers proved their specific charge.
He explained why he nonetheless voted to acquit: "Article II, Section 4 must have force. It tells us the President, Vice President, and civil officers may be impeached and convicted. Donald Trump is no longer the president. Clearly that mandatory sentence cannot be applied to somebody who has left office. The entire process revolves around removal. If removal becomes impossible, conviction becomes insensible." Yet he said that Trump "didn't get away with anything yet" since Trump would remain subject to the country's criminal and civil laws.
When there was a proposal for an independent commission to investigate the January 6 United States Capitol attack, McConnell sought to organize Republican senators to filibuster it, and on May 28, 2021, he voted against its creation.
McConnell's relationship with the Biden administration has been portrayed in media as one of comity. Biden has described McConnell as "a friend, colleague and 'man of his word.'" McConnell has praised bipartisan legislation they worked on together, and was the only Republican to attend the 2015 funeral of Biden's son Beau Biden.
In October 2021, McConnell helped pass a bill that extended the debt ceiling. He convinced 11 Republicans to vote with the Democrats for it, without which the United States would have defaulted on its debts.
McConnell stepped down as Senate Republican leader in 2024, months before the 2024 United States elections. John Thune was elected to succeed him after Republicans regained the majority in the 2024 U.S. Senate elections.
In late 2024, McConnell published an opinion article on American power and what he sees as the foreign-policy mistakes of former presidents.
McConnell has been described as largely irrelevant in Trump's second term. He has voted against three of Trump's cabinet nominees: Pete Hegseth for Secretary of Defense, Tulsi Gabbard for the Director of National Intelligence, and Robert F. Kennedy Jr. for Secretary of Health and Human Services.
In February 2025, McConnell announced he would not seek reelection in 2026 and planned to retire at the end of his term in 2027.