By Jeff Mason PORTLAND, Ore. (Reuters) – U.S. President Joe Biden warned that former President Donald Trump’s hold on the Republican Party would spill into state government on Saturday during an event to boost Democrat Tina Kotek in Oregon’s tight race for governor. Biden, who is finishing a western travel swing that included stops in Colorado and California, came to Oregon in part to help Kotek, who supporters hope will keep the governorship in Democratic hands in a state the president won handily in 2020. Kotek is running against Republican Christine Drazan and an independent candidate, Bets…