This much is clear: running for president is bad for Joe Biden’s popularity.

In January 2018, 30 percent of Americans surveyed by the NBC/Wall Street Journal Poll had a “very positive” view of Biden. Today, four months after the former vice president launched his 2020 presidential bid, he’s dropped to just 11 percent in that category.

Biden has been down this road before. The 76-year-old career politician was an early front-runner for the Democratic presidential nomination in 1988. He ended that campaign before voting began. He ran again 20 years later and scored just 4 percent in the Iowa caucuses. The New York Times has just reported that former President Barack Obama recently warned Biden’s senior campaign advisers “to make sure Mr. Biden did not ‘embarrass himself’ or ‘damage his legacy’ during the [2020] campaign.”

Obama’s White House “wingman” isn’t the only current Democratic candidate to see his good vibes diminish since joining the race. Vermont Sen. Bernie Sanders has fallen from 21 percent of respondents feeling “very positive” about him in 2017 to 14 percent now.

Massachusetts Sen. Elizabeth Warren, however, has held on in the “very positive” category, maintaining 14 percent over the past year.

These popularity numbers do increase, of course, when you add in respondents who say they are “somewhat positive” about a candidate. Overall, Sanders is at 37 percent positive, Biden at 34 percent and Warren at 31 percent.

President Donald Trump stands at 28 percent “very positive” in the survey. Forty-three percent of poll respondents approve of Trump’s performance in office and 55 percent disapprove.

Other data in the latest NBC/Wall Street Journal Poll also indicate the eventual Democratic nominee, whoever it is, will have reason to be optimistic about the 2020 general election. Sixty percent of respondents say the country is “off on the wrong track.” And 64 percent -- up 7 percentage points since 2017 -- say “free trade is good for America,” suggesting they disapprove of the president’s “trade war” approach to China and other countries.

The NBC/WSJ August 2019 poll, which surveyed 1,000 Americans, has a margin of error of about 3 percent. Check out the entire poll and its methodology.

A variety of recent national polls indicate that Biden remains the front-runner in the race for the Democratic nomination. Sanders, Warren, California Sen. Kamala Harris and South Bend, Ind., mayor Pete Buttigieg also are among the top tier of candidates.

-- Douglas Perry

@douglasmperry

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