I agree with you, he mainly dropped from the race because it was no longer an effective avenue to advance his ideas.

I do have to contest the first part of your statement - it's wishful thinking to see him having won this race. You're correct that he enjoys a broad base of bipartisan support, but the combination of turning on Trump, leaving the Republican party, and having a well-recognized opponent imperiled his chances in that district. He would have had to snag approximately 25% of the Democratic vote and 45% of the Republican vote to achieve that feat.