Any Democrats who beats Trump might still have to face Mitch McConnell

A Democrat could unseat President Donald Trump in 2020, but they might still have to contend with Washington's most immovable object: Senate Majority Leader Mitch McConnell.Republicans control the Senate by a fairly wide margin, making it a lofty challenge to flip Congress's upper chamber even if they hold onto the House of Representatives and take back the White House.McConnell spent years blocking the Obama administration and is now using his power to turn the Senate into a “graveyard” for progressive legislation that makes its way out of the House.Visit BusinessInsider.com for more stories.WASHINGTON — Democratic presidential candidate and former Vice President Joe Biden mused that if he unseats President Donald Trump and takes the White House in 2020, then congressional Republicans will have an “epiphany” that brings them together to work with Democrats.Based on the past decade in Washington, especially taking into consideration which longtime lawmakers are in charge of the Senate, Biden's thinking is highly unrealistic.Read more: Joe Biden is running for president in 2020. Here's everything we know about the candidate and how he stacks up against the competition.Senate Majority Leader Mitch McConnell has for years had a one track mind set on confirming federal judges in the mold of textualist jurists like the late Antonin Scalia. It began when McConnell used his newfound authority during the Obama administration to keep open as many vacancies as possible, betting big on the prospect that the next president would be a Republican.And McConnell got his wish. Since the Trump administration began, McConnell has confirmed lifetime-appointed judges at breakneck speed, including two Supreme Court justices.While he shepherded through legislation during the first two years of Trump's term, like tax cuts and repeated, albeit unsuccessful, attempts to pass healthcare reforms, the judicial confirmations have always been McConnell's primary goal.Since Democrats took control of the House of Representatives at the beginning of the year, McConnell has largely shelved big-ticket Republican legislation in favor of sticking to his bread and butter: confirming more judges. He is not even considering partisan legislation that comes out of the House, going as far as to liken himself to the “Grim Reaper” of liberal policies.What McConnell has done has been a primary source of Democrats' anger for several years. But Republicans love it.McConnell's advancement of conservative judges, which Republicans are adamant will ensure a generation-long preservation of conservative policy despite whatever the future holds, is highly popular on the right and particularly with Trump, who views the many confirmations as big wins.Taking back the Senate might prove to be too difficult for DemocratsSo if one of the 22 Democrats running for president manages to unseat Trump, they very well might have to once again contend with McConnell the way Obama did and the way House Democrats do now.Democrats want to take back the Senate, but they face an uphill battle. The Senate stands are 53 to 47, meaning Democrats would have to flip four seats in 2020 — or three seats and use a Democratic vice president as the tie breaker.Read more: The Democrats' presidential nominating process is such a confusing mess that 2020 candidates are spending tons of money to navigate itAnother obstacle to retaking the Senate is the fact that many top recruits for Senate races in battleground states are opting instead to run for president, much to the ire of Senate Minority Leader Chuck Schumer. In states like Montana with Governor Steve Bullock, Colorado with former Gov. John Hickenlooper, Texas with Beto O'Rourke, and Georgia with Stacey Abrams, candidates are opting not to run for Senate and are setting their sites on other offices.Another problem for Democrats might be Alabama, where Sen. Doug Jones faces a very tough reelection fight in a deep-red state.And if Democrats manage to take the Senate back by a razor-thin margin, keeping them all in line might prove to be just as difficult as it has been in the Trump era. Senators like Joe Manchin of West Virginia and Kyrsten Sinema of Arizona have repeatedly sided with Republicans on hot-button issues and high-level confirmation votes.How Democrats plan to flip the Senate is still a work in progress. How they plan to retake the White House is up in the air as almost two dozen candidates fight for the nomination, only to face Trump, an incumbent with massive resources and an otherwise strong economy.Either way, next four years after Trump could be a lot harder for Democrats than they think.