Can an unconfirmed transaction that only Blockchain.info shows be manually re-broadcast?
Old question, but answer might be helpful for someone.

To get a raw transaction append:

?format=hex


to the transaction URL.

For example:

https://blockchain.info/tx/1b087a7aebdd06740bd4ffefba076562b582a97f02cedf2cd32f53f7eb0b3c8c?format=hex