&lt;span&gt;Florida State QB&lt;/span&gt;&lt;strong&gt;&#160;Jameis Winston&lt;/strong&gt;&lt;span&gt;&#160;-- frontrunner for the&#160;&lt;/span&gt;&lt;strong&gt;Heisman Trophy&lt;/strong&gt;&lt;span&gt;&#160;-- is being investigated for felony sexual assault, TMZ has learned.&#160;&lt;/span&gt;&lt;span&gt;&lt;/span&gt;