The numbers suggest that, as Washington and the states weigh various responses to the coronavirus, Republican candidates are facing a tough campaign-year balancing act. They are left to figure out how closely to tie themselves to a less-than-popular president who is seeking re-election while getting low marks for his handling of the pandemic.
The movement has been fairly clear, and it could be significant in the fight for control of the Senate, where Republicans hold a 53-to-47 edge.
Back on Feb. 5, when there wasn't yet a single reported case of COVID-19 in the United States, the Cook Political Report listed three Republican Senate seats as "tossups" and three more as "lean Republican." By the end of April, that had shifted to four Republicans in "tossup" races and four more in "lean Republican" races. (The Democratic seat ratings didn't move in that time.)
In February, the seats of Martha McSally of Arizona, Cory Gardner of Colorado and Susan Collins of Maine were rated tossups. The seats of Thom Tillis of North Carolina and Kelly Loeffler of Georgia and the open seat in Kansas left by the departing Pat Roberts were all rated as leaners.
At April's end, Tillis' race had moved into the tossup category, and two new seat had moved into the GOP- leaning group, those of Joni Ernst of Iowa and Steve Daines of Montana.
That's pushed the number of endangered Senate Republicans from six to eight in a body where a three-seat swing could mean the loss of a majority, depending on what happens with the White House.
Of course, the entire campaign will be unfolding during or in the wake of the pandemic, but some of the races, in particular, may present special challenges
In Arizona, McSally has faced a tough race from the beginning against Democrat Mark Kelly, a former astronaut and the husband of former Rep. Gabby Giffords, but the numbers don't look good for her right now. The latest RealClearPolitics polling average shows McSally down by 8 points to Kelly in head-to-head polling.
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And the pandemic has created political waves in Arizona recently. Last week, the state's health department was roundly criticized when it asked a local group of academics who were modeling the virus in the state to stop their work. (The state later changed its mind and put the team back to work.) Meanwhile, McSally herself was captured on tape at an event saying she wouldn't commit to supporting additional financial support for state and local governments during the pandemic.
In North Carolina, Tillis won his Senate seat in 2014 by a narrow 1.5 points, but the RealClearPolitics polling average shows him trailing Democratic nominee Cal Cunningham by less than a point now.
Tillis has faced some political challenges during the pandemic, as well. After backing Democratic Gov. Roy Cooper's shelter-in-place and phased-in reopening plans, Tillis was attacked from conservatives on the right, never a good thing in an election year when partisan tensions are high. And with summer tourism season coming to the state, the reopening debate is likely to linger as a major issue he'll have to navigate.
In Montana, Daines faces a new reality because Gov. Steve Bullock entered the race in March. In 2014, Daines walked to an 18-point win, but the latest poll from Montana State University and the University of Denver shows Bullock with a 7-point lead.
Furthermore, the coronavirus gives Bullock a nice perch from which to campaign. He gets plenty of airtime as the state's chief executive during an emergency. And, so far anyway, the story out of Montana has been a good one. As of Friday, there had been a total of 462 COVID-19 cases in the state and 16 deaths related to the virus.
To be clear, the coronavirus is going to play an important role in every campaign this fall. The scope of the impacts extends well beyond health to the economy and a broad range of other topics, from education to voting systems. It touches every part of the country.
But the early data suggest that Republicans have more to fear politically.
A range of polls consistently show that most Americans disapprove of President Donald Trump's handling of the crisis. And thus far, Washington's struggles to craft a consistent plan and message seem to be weighing most heavily on the party that is in control.