Two new Michigan polls show a close Senate race; our forecast slips to 65 percent

Two surveys of the open Michigan Senate race, both finishing on September 14, found Democrat Abdul El-Sayed narrowly ahead of Republican Mike Rogers. A Washington Post/George Mason University Schar School poll of 803 likely voters, fielded September 10-14, had El-Sayed at 48 percent and Rogers at 45 percent. An Emerson College poll for Nexstar, 1,000 likely voters fielded September 12-14, had El-Sayed at 48.2 percent, Rogers at 45.7 percent and 0.3 percent for other candidates. Both gaps are small enough that the race reads as close rather than as a clear lead for either candidate.

Our model now gives El-Sayed a 65 in 100 chance of winning the seat, with a mean margin of D+2.4 and a 5th-to-95th percentile range running from R+7.4 to D+12.1. The previous run, from 6:32 AM ET on Wednesday, had the Democrat at 66 percent with a mean margin of D+2.5. That is a one-point move, which is to say close to none. The direction is worth noting only because it continues a slow drift: this site reported the forecast at 70 percent on September 10.

The substance of these two polls is consistent with what our average already carried. Neither shows a margin much different from the model's central estimate, and neither pushes the distribution in a new direction. The range remains wide in both directions, with outcomes from a mid-single-digit Republican win to a double-digit Democratic one inside the middle 90 percent of our simulations.

Michigan matters to the chamber picture. Our model gives Democrats a 47 in 100 chance of Senate control and Republicans 53 percent, with a mean of 50.0 Democratic seats. Democrats need 51 seats for control; Republicans need 50, because the vice president is a Republican and a 50-50 tie goes their way.