Former first lady Melania Trump discusses her reaction to the threats against her husband on 'Fox & Friends.'

"Events, dear boy, events." That’s what the late British Prime Minister Harold Macmillan said remain the greatest challenge facing a political campaign. Back in January 2023, I wrote that the 2024 campaign would likely hinge less on the actual campaigns than on a set of "Known-Unknowns," – the economy, Ukraine, and the Middle East wind up playing out.

At the time, it seemed that President Joe Biden would be running and the GOP nominee wasn’t known. Two years later, Biden has been replaced by Vice President Kamala Harris, and former President Donald Trump easily sailed to the nomination – but those Known-Unknowns remain, even as polls show minimal shifts in public opinion.

There are four that are likely to change voter’s behavior – or not – in the coming weeks.

THE NUMBERS DON'T LIE: TEAMSTERS IN KEY BATTLEGROUNDS SUPPORT TRUMP OVER HARRIS

Will further actions by the Federal Reserve change views of the economy? The Fed just announced a 0.5% cut in interest rates, which helped cause Wall Street to achieve an all-time high, and suggested that the economy has done better than many thought just a few months ago. Polls that had recently given Trump the edge in who the voters trust more on the economy now suggest that Harris and Trump are at parity.

The race between Vice President Kamala Harris and........

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