THE KAMALA HARRIS BOOM-AND-BUST CYCLE. If the polls are right, support for Vice President Kamala Harris, the new Democratic nominee for president, is booming. After months of President Joe Biden trailing former President Donald Trump in the RealClearPolitics average of national polls, Harris now narrowly leads Trump. The last six polls in the average show Harris ahead. Although this is exactly what Trump’s pollster predicted would happen in the immediate aftermath of the Biden-Harris switch, it is still disheartening for Republicans.

How happy are Democrats and their allies in the press? Consider this, from a longtime contributor to MSNBC’s Morning Joe on Wednesday: “Watching the VP, it was mesmerizing in the sense I’ve never seen a rally like that, either on TV or in person. And watching it, you could just sense the power in the all — and it was the power of joy, the power of laughter, the power of hope for the future.” That’s happy.

But GOP strategists might take heart in what could be called the Harris boom-and-bust cycle, established the only other time Harris ran for national office. She was a candidate for the 2020 Democratic presidential nomination, but her campaign began and ended in 2019. Still, in one brief period, she shot up from back in the pack to close to the lead, only to disappear just as quickly. 

Harris declared her candidacy in January 2019. By April, her support stood at 5% in the CNN poll of the Democratic primary race. (All the numbers here are from subsequent CNN polls, conducted with the same methodology.) By May, Harris had climbed to 8%. Then, in the June poll, she jumped up to 17%. There was no poll in July, but by August, Harris was back down to 5%. She meandered around after that — 8% in September, 6% in October, 3% in November — and by December, she was out of the race.

Harris’s brief boom came after a Democratic debate in which she accused Biden of racism for opposing school busing back in the 1970s. For a moment, Harris became a progressive hero, until, with increased exposure after the debate, voters got a closer look at her. They didn’t really like what they saw, and her fall began.

What does that experience mean for the presidential race today? First, the situation is different in that this time, Harris has the entire Democratic Party, the entire Democratic establishment, and almost all of the media backing her up. For them, she is the whole game. They will not let her fail if success is at all possible.

In addition, in the 2019 Democratic primary, when a voter tired of Harris, he or she could switch support to another Democrat. When Harris began to wear badly — and it happened very quickly — the Democrats who supported her simply moved on to another Democrat.

Now, if Harris begins to wear badly on voters, there is no other Democratic candidate to go to. Would those Democratic voters then decide to vote for Trump? That seems highly unlikely. So Harris might benefit from the fact that her supporters have nowhere else to go.

On the other hand, a significant part of Harris’s rise appears due to new support from independent voters. A recent CBS News poll in July found Trump leading Biden among independents 54% to 44%. Now, Harris is tied with Trump among independents, 49% to 49%. It is those voters who might become disillusioned with Harris. If they switched from Trump to Harris in recent polls, they might switch again.

Of course, Democrats are determined to make sure that doesn’t happen. Why do you think Harris has not taken a single question from a journalist since Biden endorsed her and she became the instant presumptive nominee on July 22? Harris is doing rallies, speaking off a teleprompter. She’s appearing with her new running mate, Gov. Tim Walz (D-MN). But she’s not going into any situation where she might face some unexpected factor, and her reaction might offer voters a closer look at her as a person and a candidate. That is what happens in the long, grueling process of running for president. This time, after the Big Democratic Switch, party strategists know that if they can just keep Harris away from any unexpected exposure, away from any surprises, the honeymoon might keep going for 90 days, long enough for Harris to win. 

So look for Democrats to keep Harris under wraps as long as possible. It’s their best bet to keep history from repeating itself.