With eight days to go until the U.S. election, President Donald Trump addressed three boisterous rallies in Pennsylvania on Monday, while Democrat Joe Biden made a low-key appearance in the state considered crucial to the chances of victory for both men. 

"We win Pennsylvania, we win the whole ballgame," Trump told a rally in Martinsburg, as he predicted a win in the state despite trailing Biden in most opinion polls. 

Trump touted a poll from Rasmussen, which has long gone against the flow of more established polling companies to give him favorable numbers, and said many "hidden Trump voters" would back him in the polling booth on November 3. 

Biden made a small-scale appearance in the city of Chester, near Philadelphia, meeting with about a dozen campaign volunteers and speaking with reporters. Biden said he was "not overconfident about anything" and "with the grace of God" he would win Pennsylvania, the state where he was born. 

"I think we're going to win Michigan, I think we're going to win Wisconsin. I think we're going to win Minnesota. I think we have a fighting chance in Ohio. I think we have a fighting chance in North Carolina. We have a fighting chance in Georgia," Biden added, referring to other election battleground states. 

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Biden also stepped up his criticism of Trump's handling of the coronavirus pandemic that has killed more than 225,000 people in the United States, saying: "The bottom line is, Donald Trump is the worst possible president, the worst possible person to lead us through this pandemic." 

Trump again asserted that his administration was "doing a great job" against the pandemic and that the U.S. was "absolutely rounding the corner." He accused Biden of wanting to return to widespread lockdowns that he said would harm the economy. 

Despite Biden's solid lead in national opinion polls, the contest appears tighter in the most critical battleground states that could decide the outcome. A Reuters/Ipsos poll conducted from October 20 to 26 gave Biden a narrow advantage over Trump in Pennsylvania. 

A state where a majority of voters can swing toward either major party, Pennsylvania has been heavily courted with frequent visits by both candidates. Trump went from Allentown to Lititz and then finally to Martinsburg, all towns outside the large suburban hubs where the race may be decided.  

Trump also planned multiple stops in Michigan and Wisconsin this week, as well as visits to Arizona, Nebraska and Nevada. 

Trump told reporters he expected to win Pennsylvania by a larger margin than the 0.72 percent victory he achieved in defeating Democrat Hillary Clinton in 2016.

Addressing supporters, Trump touched on what he called "an existential" issue for Pennsylvania, Biden's comment during last week's presidential debate that if elected he would "transition" the United States away from oil and natural gas. 

"He wants to go with windmills that are made in Germany and China," Trump said, adding: "Biden's plan is an economic death sentence for Pennsylvania's energy sector." 

In Chester, Biden defended his stance, saying: "I'm not shutting down oilfields. I'm not eliminating fracking. I'm investing in clean energy." 

Biden previously said the country should eventually replace oil with solar, wind and other forms of non-polluting power, adding that his plan for a more climate-friendly economy would create high-paying jobs and boost U.S. businesses. 

(With input from Reuters, AFP)