Biden Beats Trump by 8 Points? Poppycock.

On Thursday, former Vice President Joe Biden announced his candidacy for president in 2020. The latest Morning Consult/Politico poll puts him eight points ahead of President Donald Trump, but that's no reason for Biden to start celebrating. Polls this early into a presidential race have almost no bearing on the final results of the election.

The poll, conducted between April 19 and April 21 among nearly 2,000 registered voters, found Biden with 42 percent against Trump's 34 percent. This poll may show Biden's strength at this point in the race, but 19 months is a long time, and Biden may not even be the Democratic candidate in November 2020. (He leads among Democrats now, but that is very likely to change.)

As John Merline over at Issues & Insights pointed out, at this point in the 1984 presidential election, astronaut and Sen. John Glenn (D-Ohio) was handily beating President Ronald Reagan. According to The New York Times, Glenn led Reagan, 54 percent to 37 percent. The eventual Democratic nominee, Walter Mondale, also beat Reagan, 49 percent to 43 percent, in July 1983.

Those polls were more than reversed in the general election of November 1984. Reagan cruised to re-election with almost 59 percent of the vote, winning every state except Mondale's home state of Minnesota. His 525-electoral-vote victory remains the second greatest landslide in American history, behind Franklin Delano Roosevelt in 1936 — not counting George Washington's unanimous wins in 1789 and 1792.

In March 2003, a Quinnipiac poll found that an unnamed Democratic candidate would beat incumbent President George W. Bush, 48 percent to 44 percent. Bush beat Sen. John Kerry (D-Mass.), 50.7 percent to 48.3 percent in November 2004.

Even President Trump's current low approval rating does not bode ill for 2020. "There are several examples when presidents who had nationwide approval ratings in the 40% range in the year before the election won a second term, including Ronald Reagan, Bill Clinton and Barack Obama," Gallup's Jeffery Jones reported. "All managed to get to 50% approval by the time of the presidential election."

Trump's nationwide approval in Gallup's poll, 45 percent, is identical to Barack Obama's approval rating at this time in his presidency. Reagan's approval rating at this point in the 1984 election was lower than Trump's is now, and Clinton's approval rating at this point in the 1996 election was only two points above Trump's current score.

None of this guarantees a Trump win, of course, but it should remind political prognosticators to hesitate before reading too much into a poll this early in a presidential election. The Drudge Report's headline screamed the news of this pro-Biden poll, but Uncle Joe is far from a done deal — even if he beats the other Democrats.

Follow Tyler O'Neil, the author of this article, on Twitter at @Tyler2ONeil.