Next Tuesday's Wisconsin Senate primary is a bit anticlimactic. Over the past few weeks, all the other major Democratic candidates dropped out of the race and threw their support behind Lt. Gov. Mandela Barnes, who'd long been seen as a narrow frontrunner though polls had still shown more than a third of voters were undecided.

With Barnes now the presumptive nominee, his challenge against Republican Sen. Ron Johnson officially starts. Johnson is the most vulnerable GOP incumbent this cycle, and he's the only sitting senator of either party representing a state that voted for the opposite party for president in the most recent election. The two-term senator's own numbers in the state remain low — a warning sign for any incumbent. The most recent June Marquette University Law poll put Johnson at 37% favorable/46% unfavorable. Comparatively, President Biden is at 42% fav/54% unfav, with his job approval at 40% approve/57% disapprove. That same poll also showed the race within the margin of error, with Barnes ahead of Johnson 46%-44%.

This is a race where Republicans are almost giddy

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