Four months ago, at the bottom of the coronavirus recession, President Trump’s reelection odds were dismal. Forecasting firm Oxford Economics plugged the economic numbers into its forecasting model, which predicted Democrat Joe Biden would beat Trump by the biggest landslide in 40 years.

Oxford Economics has updated its model, and the race now looks closer. In the May analysis, Biden beat Trump in the popular vote by a whopping 65%-35% margin, largely because a wrecked economy thoroughly turned voters against the incumbent president. And Biden won the Electoral College 328-210, flipping 7 states Trump won in 2016: North Carolina, Pennsylvania, Ohio, Michigan, Wisconsin, Iowa and Florida.

In the latest analysis, Biden wins the popular vote by a much narrower 52%-48%. Trump wins Missouri, while Biden retains the six other states and wins the Electoral College 318-220. Here’s the map:

This outcome would still be a convincing Biden win, but the tighter margin suggests developments of the last four months have favored Trump and left the possibility that a late surge can push Trump to victory.

What changed? Congress pushed trillions of dollars of stimulus into the economy, triggering a faster recovery than many economists expected. “The stronger-than-expected fiscally driven economic rebound means economic fundamentals point to a tighter race than in May,” Oxford Economics now says.

In March and April, Congress passed $3.7 trillion worth of stimulus programs meant to sustain businesses forced to shut down or scale back because of the coronavirus pandemic, keep furloughed workers afloat and help most Americans with a one-time $1,200 stimulus check. That was the biggest economic bailout Congress ever passed, and it largely worked. The unemployment rate soared from 4.4% in march to 14.7% in April, but has since fallen back to 8.4%. Retail sales plunged in March and April, but they’ve since rebounded to levels higher than before the virus arrived.

The Oxford model is based on state-by-state economic conditions, including the unemployment rate and changes in per-capita income. A formula that has accurately predicted the winner in most presidential elections since 1948 then calculates the portion of the vote the incumbent president is likely to win in each state, arriving at an electoral-college tally. Oxford also models outcomes based on voter turnout that’s higher and lower than usual.

The economy has recovered in key swing states such as Michigan, Wisconsin, Ohio and Pennsylvania, narrowing Biden’s likely margin of victory. But much of the stimulus spending has run out, with further economic gains likely to be slow and incremental. Unemployment remains abnormally high, coronavirus is still forcing restrictions on businesses, and the recovery isn’t strong enough to put those swing states back in Trump’s column. Polls show Biden leading by a margin of about 3 points in Ohio and about 5 points in the other three states.