I prematurely accepted a job offer, what do i do?

So I've been job hunting for about a month now. I interviewed at many places, and haven't heard back from any of them until I was offered an appealing job at a really cool company. Since I haven't heard back from anyone else, I accepted it since I assumed the others weren't going to contact me back. Then all of a sudden, two job offers arrive offering way more than the one I accepted. Is it possible to pursue these offers once I've already accepted one? Would it burn a bridge if I decide to take back an acceptance?

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