Joseph R. Biden had a narrow lead in Iowa over President Trump, the two candidates were tied in Georgia, and Mr. Trump had a similarly tiny edge in Texas, according to polling released on Thursday.
The Democratic presidential nominee had a 3-point, 45% to 42% lead over Mr. Trump in Iowa, the two candidates were tied at 45% apiece in Georgia, and the president had a 3-point, 46% to 43% lead over the former vice president in Texas, according to the New York Times/Siena College polling.
Mr. Trump carried Iowa and Texas by about 9 points in 2016, and he won Georgia by about 5 points.
In Iowa’s U.S. Senate race, Democrat Theresa Greenfield had a 42% to 40% lead over GOP Sen. Joni Ernst.
In Georgia, GOP Sen. David Perdue had a 3-point, 41% to 38% lead over Democratic challenger Jon Ossoff.
In the state’s special Senate election, GOP Sen. Kelly Loeffler was at 23% support, followed by Democrat Raphael Warnock and Republican Doug Collins at 19% apiece, Democrat Matt Lieberman at 7%, and Democrat Ed Tarver at 4%.
If no candidate eclipses 50% support in November, the top two vote-getters will advance to a runoff in January.
Mr. Lieberman, the son of former Sen. Joseph I. Lieberman of Connecticut, has eschewed calls for him to drop out of the race amid fears that he could siphon enough support away from Mr. Warnock to lock Democrats out of the runoff.
In Texas, GOP Sen. John Cornyn had a 6-point, 43% to 37% lead over Democrat M.J. Hegar.
The polling was conducted from Sept. 16-22.
The Iowa results, based on interviews with 501 likely voters, and the Georgia survey of 523 likely voters have margins of error of 5 percentage points.
The Texas survey of 653 likely voters has a margin of error of 4 percentage points.