Most people are focused on the presidential hopefuls and the upcoming election that will decide who will succeed President Obama.

But the U.S. Senate is the real name of the game in this election if the winner of the White House wants to get anything done.

Consider if Hillary Clinton or Bernie Sanders wins in November and comes into office Jan. 20, 2017, facing a GOP-controlled House and a GOP-controlled Senate.

That means the new Democratic president would face a Congress set to delay, dither, obstruct, gut and torpedo initiatives and legislation — in short, the kind of Congress that President Obama has been saddled with for most of his tenure.

Then imagine if Donald Trump or Ted Cruz arrives in office facing a Democratic-controlled Senate. Now the script is gently flipped.

Such a Democratic Senate could prevent either from carrying out collective, oft-stated campaign pledges to build a bigger, longer border wall, plow more ground troops into multiple countries, repeal Obamacare or gut or eliminate the IRS, the EPA, the Department of Education and a litany of other federal agencies.

It would be harder for either to pack the U.S. Supreme Court and the rest of the judiciary with hard-core conservatives. In other words, Senate Democrats would be the firewall to halt a wholesale GOP effort to roll back the progress of the 20th century.

Senate Majority Leader Mitch McConnell wants to keep the Senate in Republican hands. He has held private meetings with GOP party leaders in which he has said that the GOP must do everything to maintain a firewall against a Democratic president.

He took the virtually unheard of step of telling GOP Senate candidates and incumbents whose seats are on the block to feel free to distance themselves from the mostly likely GOP presidential nominee, Mr. Trump, if that’s what it takes to win.

The GOP majority in the Senate is vulnerable this year as the party must defend 24 seats, while Democrats need to defend only 10 seats. A swing of just four seats to the Democratic column would put Democrats in control of the Senate and give Mrs. Clinton or Sen. Sanders some space to at least get a hearing for a legislative agenda and on prospective cabinet, department, agency and judicial appointees.

It’s those appointments, starting with the U.S. Supreme Court, that has the GOP in a nervous sweat about Senate control. The Senate, not the House, is the sole determiner of who sits on the high court and the lower courts and bags key spots in federal agencies.

These are all top-grade posts that initiate, make and implement crucial policy decisions after many in Congress are long gone. The Senate majority leader has virtually dictatorial control over which of the president’s nominees are put to a confirmation vote.

Sen. McConnell has used that power, and at one point, had held up confirmation for 150 nominees President Obama wanted to place in executive and court spots.

That’s why winning the presidency will not be enough. The White House winner will need a friendly upper chamber of Congress to have a chance to get some of the people’s work done.

EARL OFARI HUTCHINSON

Los Angeles

The writer is an author and political commentator.