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Where is Eugene McCarthy when we need him?

In 1968, McCarthy, then a U.S. senator from Minnesota, entered the New Hampshire Democratic presidential primary as an anti-Vietnam War protest candidate against challenging President Lyndon Johnson.

McCarthy's respectable 42% second-place finish in the primary so shocked LBJ that he soon withdrew from the race and announced he would not seek a second term.

McCarthy did not receive the Democratic nomination in 1968. Robert Kennedy entered the race after the New Hampshire primary, was later assassinated, and Vice President Hubert Humphrey was nominated. Republican Richard Nixon ultimately won the 1968 election in a close vote.

Nevertheless, McCarthy had done a great service to his party and his nation.

Today, someone — and another Minnesota Democratic senator, Amy Klobuchar, seems to me the obvious choice — needs to do what McCarthy did: challenge an incumbent president who does not realize how unpopular his renomination is with the public.

For a variety of reasons, Robert Kennedy Jr., who is running against President Joe Biden, is not the right person to serve this role. Kennedy is receiving Biden-protest support. But for most Democratic voters, he is an impossible choice, a nonstarter because of his stance on vaccines among other matters.

Klobuchar, who ran effectively in 2020 before bowing out and endorsing Biden, would be the perfect alternative candidate in this cycle. She already has the necessary name recognition and national contacts and is acceptable to most of the divergent perspectives within the Democratic Party.

Despite liking Biden and admiring what he has accomplished, most Democrats do not want the president to run for re-election. It is because of his age — he is already, at 80, the oldest president in American history — and because of the whiff of scandal from the Hunter Biden saga.

For these same reasons, Biden is a weak candidate for the general election. Lingering inflation and dissatisfaction with the economy generally, which are also pulling down his poll numbers, are actually trending in a positive direction and may turn around in time for the general election in 2024. But the other concerns will not go away.

Biden is the only potential Democratic Party nominee who might actually lose to Donald Trump, the likely Republican nominee.

I share the common feelings about Biden. I like him and I think he has done a good job. But I believe Biden is too old to run again. He should retire in 2025, as I'm doing (I'm in my 70s).

A strong showing by Klobuchar in the early primaries might bring Biden to his senses and drive him from the race. That would lead the way for Klobuchar, or someone else, to be nominated.

Ironically, an alternative nominee could run on Biden's legacy more effectively than Biden can.

A Klobuchar candidacy would also positively impact the Republican presidential nomination race. Reports indicate that attacks on Trump's electability, which should be undercutting his campaign, are failing to persuade Republican voters who know perfectly well how damaged a candidate Trump would be in the general election. The reason Republican voters are not worried about electability is that many Republicans regard Biden as so weak a candidate that any Republican, including Trump, would beat him in the general election.

A credible challenge to Biden, however, would open up Republican voters to the reality that Trump cannot win a general election. That realization may be the only way to deny Trump the Republican nomination and finally end his stranglehold on the party.

Denying Trump the Republican nomination has to be a high priority for anyone who loves America. Trump is a menace, but the country is so divided that any nominee of one of the two parties stands a good chance of winning. If nothing dramatic changes, Trump could be re-elected president in 2024.

It is not an easy thing to be courageous in politics. Klobuchar is running for re-election to the Senate, which would be complicated, if not precluded, by challenging Biden.

But Eugene McCarthy risked a great deal in 1968 and ultimately gained nothing for himself.

Yet, I'm sure he never regretted what he did.

McCarthy put America first.

Now is the time for someone in the Democratic Party to do the same.

Amy, your country needs you. Run!

Bruce Ledewitz is a law professor at Duquesne Kline School of Law in Pittsburgh.