Small-business health exchanges run by the federal government will not open for online enrollment until November, the Obama administration said Thursday. But applicants may still enroll by phone, mail or fax beginning Oct. 1. The White House had initially planned to launch these marketplaces, which serve businesses with fewer than 50 employees, on Tuesday, the same day that individual marketplaces go live. While the Web sites of the federally run exchanges will go live on that date, an administration official said that the "feature of shopping for and comparing plans online will be available starting Nov. 1."