Four polls released on Sunday and Monday show Democratic nominee Joe Biden with a strong nationwide lead over Republican President Donald Trump.

On Monday, Monmouth University released a survey that showed Biden with a 5-point edge over Trump, 50%-45%, while a poll from TheHill/HarrisX had Biden with a 5-point lead over the incumbent, 45%-40%.

On Sunday, a New York Times/Siena survey showed Biden with an 8-point lead over Trump, 49%-41%, while an ABC News/Washington Post poll had Biden with a 10-point edge, 54%-44%. When factoring third-party candidates, the ABC News/Washington Post survey showed Biden at 49%, Trump at 43%, Libertarian Jo Jorgenson at 4% and Green Party candidate Howie Hawkins at 3%.

On Tuesday evening, Biden and Trump will square off for their first debate.

In September 2016, Democratic candidate Hillary Clinton had a 6-point edge over Trump prior to the first debate, 43% to 37%. Clinton won the popular vote over Trump, 48.2%-46.1%.

The debate will be a crucial moment for both Biden and Trump. Biden will likely hit Trump over his response to the COVID-19 pandemic and a recent report about Trump's tax returns. Trump will likely attack Biden over his past support for free-trade deals and his tenure as vice president in the Obama administration.

Recent swing state surveys show some dire signs for Trump. A New York Times/Siena survey in Pennsylvania showed Biden with a 9-point lead over Trump, 49%-40%. A recent NBC/Marist survey shows Biden up 8 points in Michigan, 52%- 44%. Trump won both states by a narrow margin in 2016.

Meanwhile, the race is tighter in the Sun Belt. A Susquehanna survey released Tuesday showed Biden with a 3-point lead in Florida, 46%-43%. A Meredith College poll shows both candidates even in North Carolina. Polls have also encouraging for Biden in traditionally red states Arizona, Georgia and Texas.