Three months ago, as the presidential primaries were getting underway, President Joe Biden was trailing former President Donald Trump in the polls nationally and in battleground states, and concerns about his age were coming to the fore. The optimistic view for Biden was that once the presidential primaries were over, and it became clear that the choice was a 2020 rematch, the polls would move in his direction. But the polls have changed little. In fact, a new set of battleground polls from The New York Times/Siena College shows Biden trailing in all but one of the battleground states, with a lead for Trump as high as 12 points in Nevada.In this installment of the 538 Politics podcast, the crew asks why the end of the primaries, weeks of Biden campaigning and millions spent on advertising have changed the polls little. They also preview Tuesday's primaries in Maryland and West Virginia, in particular a very competitive Democratic Senate primary in Maryland.Learn more about your ad choices. Visit megaphone.fm/adchoices