Finishing a sentence with て


来年、フルマラソンに挑戦しようと思って Next year, I'm thinking of trying to run in a (full)
marathon.

Hopefully an easy one for you all. I'm curious why this sentence ends in 'て'
and not 'ている/ています'. My (uneducated) guess would be that perhaps in casual /
spoken Japanese, the 'いる／います' is dropped.

Or is there a nuance / mood provided by it?

Thanks for your help!

