Sen. Chuck Grassley, who served with then-Sen. Joe Biden for nearly three decades, sees a possibility for advancing bipartisan legislation during the president-elect’s administration.However, those opportunities will be diminished if Biden bows to pressure from the progressive wing of the Democratic Party, the Iowa Republican said Tuesday.Grassley, who returned to the Capitol on Monday following a two-week isolation after testing positive for COVID-19, made his comments during a virtual presentation to more than 60 members of the Iowa Taxpayers Association.If President Biden serves as he did as a senator, Grassley said, “there’s a great deal of opportunity to get bipartisan product.”If his response to progressive Democrats’ planks in the party’s platform — “I mean the Sanders platform” — are an indication of how Biden will lead, then Grassley’s optimism is dampened.“He more or less just gave in to them in every respect,” Grassley said about the progressives, including Vermont Sen.