The Metropolitan Transportation Authority yesterday voted to approve a fare hike and toll increase that many commuters, and more than 100 elected officials, have urged it to stave off at least until next spring. Under the plan, approved by 12 out of 14 board members, the base fare for subways and buses will remain at $2. About 86% of straphangers who purchase discounted passes, however, will pay more at the turnstile beginning March 2.