The nomination process for the U.S. presidential election in November will formally begin Monday when Republicans in the state of Iowa express their preferences at precinct meetings, with all eyes on whether any of the remaining challengers stand a chance against Donald Trump. Amid conditions that have seen blizzards and temperatures that dropped to about minus 30 C in recent days, Republican voters in the Midwest rural state will gather for the meetings, known as caucuses, in places such as school gyms and churches. The first-in-the-nation nomination contest, which could be the coldest since …