Theories have been launched all over creation over why and how Vice President Kamala Harris’s campaign went from spectacular to one that took it on the chin on Election Day.

My theory, for what it’s worth? She became boring.

Here’s my point. As her campaign concluded, it began to dawn on me that I had heard it all before. Many times, in fact. She seemed to rely too heavily on applause lines and cliches.

To wit:

• There’s more that unites us than separates us.
• I know Donald Trump’s type.
• I have only had one client in my years in public service: you, the people.
• Donald Trump is an unserious man.
• I never have asked what party people belonged to.  I only asked, “Are you OK?”
• When we fight, we win!

I am sure there were many more examples. To be candid, I don’t remember them because I nodded off frequently during Harris’s rallies later on in the campaign.

I admit to being caught up in the excitement of Harris’s campaign after President Biden bowed out during the summer. My enthusiasm for her never waned and I voted proudly for her and for her running mate, Minnesota Gov. Tim Walz.

But as I look back now just days after their loss, I am left only to wonder if Harris — and Walz, too — relied too heavily on the same ol’ applause lines that got our attention … but which had a limited lifespan on the trail that leads to the White House.

Make no mistake: Campaign-trail boredom is a deal breaker.