By James Oliphant and Nandita Bose WASHINGTON (Reuters) – The latest legal challenge to Donald Trump’s campaign for a second term as president seems likely to hand the 2024 Republican frontrunner even more firepower in his quest to win his party’s nomination. The Colorado Supreme Court ruled on Tuesday that the former president was barred from its state ballot for engaging in “insurrection” due to a rarely used constitutional provision, an unprecedented decision that the conservative-led U.S. Supreme Court could overturn. Donors and political analysts from both major parties said the ruling wo…