It seems like a long, long time ago that Joe Biden was running for president, running as a rock-solid centrist. He won the nomination mainly because he wasn't Bernie Sanders who his own party thought was playing deep left field and couldn't win in the general election. But now, just over six months into his presidency, Joe Biden has become what Bernie Sanders confidently predicted he would become: the most progressive president since FDR.

Except that's not who Americans thought they were voting for. Voters don't like thinking they've been tricked. Which bring us to a recent poll that doesn't look good for Joe Biden and his party.

The poll, by ABC News/Ipsos taken in mid July, finds that a majority of Americans – 55 percent – say they're pessimistic about the direction of the country. But as recently as early May, only 36 percent said the same thing to the same pollsters. If your stock portfolio dropped that much in so short a time, you'd be more than a little unsettled. After going through the poll, that's how Democrats should also feel.

In May, according to ABC News, "Americans were more optimistic than pessimistic by a 28- point margin. Optimism is now under water by 10 points."

And here's the really bad news for the president and his party: "The decline in optimism has occurred across the board among Democrats, Republicans and independents. Optimism is down about 20 points among Democrats and Republicans and down 26 points among independents," according to ABC News.

If independents really are in play, Democrats had better take notice. They'll need not only strong support from their own base but also from those independents if they want to hold on to control of the House and not lose seats in the Senate. A lot can happen between now and November 2022, but right now, if independents aren't optimistic about the future, Democrats have reason not to be optimistic either.

Maybe you've heard the rumblings – the comparison of Joe Biden's presidency to that of another Democrat, Jimmy Carter. Jimmy Carter was a decent human being, but if you're a president who came after him, you don't want your presidency compared to his, which as you know, lasted only one term.

So why have so many Americans fallen out of love with Joe Biden. Well, for openers, they never really were in love with him in the first place. Biden didn't get elected because Americans saw him as a visionary or a man of great wisdom and charisma. They voted for him because he wasn't Donald Trump. And they figured they were getting the moderate he told them he was. Now they're seeing the career politician they voted for.

Here's what else they're seeing: out of control crime in big and not-so-big cities across America; a mess on the southern border; homelessness that is encroaching on all sorts of neighborhoods that once didn't have that problem; the Delta variant; confusion over who needs to wear masks and who doesn't; higher prices at the food store and the gas station; and those multi-trillion dollar spending bills the president is trying to get through Congress.

Even Franklin Roosevelt, the man Joe Biden seems to be channeling, would have a tough time winning two times let alone four times with all that hanging around his neck.

When Jimmy Carter was president there was talk about a "national malaise." Americans, an optimistic people, don't like that kind of thing. It's a big reason Carter lasted only four years. If the term "national malaise" pops up again this time around, Joe Biden won't only be channeling FDR; there's a good chance he'll also be channeling Jimmy Carter.

And if the next election is about "the economy, stupid," as James Carville famously once said, then Democrats have one more thing to worry about. While the overwhelming majority -- 88 percent -- of Democrats approve of how Biden is handling the economic recovery, (unsurprisingly) only 16 percent of Republicans do – but most importantly, only 49 percent of independents approve.

Americans still like Joe Biden, at least they like him more than they ever liked Donald Trump. According to Gallup, in mid-June, Biden's approval rating was 56 percent. But in July it was down six points to only 50 percent. In June, 55 percent of independents approved of Biden's job in office. In July it dropped seven points to 48 percent.

According to exit polls, Americans not aligned with either major party favored Joe Biden for president by 13 percentage points. That's the biggest margin among independents in more than three decades.

Six months into his presidency, independents are on the move – moving away from the president they supported last year. They thought they were voting for "middle class Joe" the centrist Democrat. But that Joe Biden has been moving left pretty much from the moment he took the oath of office. That might make Bernie and other progressive Democrats happy. Not so much, though, for those independents who will have a big say about which party will win in 2022 – and two years after that.