The Cook Political Report shifted the open Pennsylvania Senate race from "toss up" to "lean Democrat" in the nonpartisan prognosticator's latest ratings published on Thursday.

Why it matters: The new ratings reflect Pennsylvania Lt. Gov. John Fetterman's (D) edge over Republican rival Mehmet Oz in the hotly contested Senate race.

Driving the news: The Cook Political Report also classifies Senate control as a "toss up," writing: "Right now, the range we see is between Democrats picking up one seat and Republicans gaining three. However, the most probable for now may be a net change of zero or a GOP pickup of one to two."

• That's a stark change from a few months ago, before primaries began in earnest in early May. At the time, the Cook Political Report "put the odds that Republicans would flip the Senate at more than 60 percent, with a gain of as many as four seats possible."
• The Cook Political Report shifted Colorado's Senate race from "likely Democrat" to "lean Democrat" and Utah's changed from "solid Republican" to "likely Republican."
• Republicans can take control of the Senate if they pick up at least one seat.

Yes, but: A number of inexperienced Republican candidates like Oz, who are backed by former President Trump, may cost Sen. Mitch McConnell the Senate majority in this year's midterms, Axios' Josh Kraushaar reports.

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