Four years ago, Bob won by outspending his competitors in a crowded field of no-name candidates. The only candidate with a track record, Mark Boughton, was too moderate to win a GOP primary, and so Bob was able to squeak out a win.

This year, Bob is basically a sacrificial lamb since Lamont became quite popular thanks to perceptions of his handling of the pandemic. IIRC it was a much less crowded field, and Bob had the money and the name recognition.