Graham PlatnerThe TOI correspondent from Washington: The abrupt collapse of Democrat Graham Platner's Senate campaign in Maine has thrown one of America's most closely watched midterm contests into turmoil and revived a recurring question in US politics: how much do allegations of sexual misconduct still matter to voters?Platner, a 41-year-old oyster farmer, harbormaster and Marine Corps veteran from coastal Maine, emerged this year as an unlikely political sensation. Running as an anti-establishment progressive with the backing of Senator Bernie Sanders, he built a formidable grassroots movement and defeated more established Democratic figures to become the party's nominee against Republican Senator Susan Collins.The race is crucial because Maine is one of the Democrats' best opportunitie