Summer Internship advice

<p>As my final summer while in college approached, I applied to a bunch of internships around the country. Last week, after the interview, I finally got the offer to one, that pays well, and it is a good opportunity. However, in between the interview and the offer, I interviewed for another position in another company, and today I got an offer from that company as well. The deal is, I accepted the offer from the first company. However, the second company would allow me to continue as a coop in the fall semester, while the other wouldn't. Now, I know if I decide not to get the job I already accepted, I will most likely never have a chance to get a full time job there, since it would be incredibly rude. So, my question is, if I politely decline the offer from the second company, how much would that affect my job perspectives in the same company for after I graduate?
I don't know if this is the right place to ask this question, but it seems to me that a lot of people here have experience with recruiting, so I was just wondering what to do before declining this offer.
Thanks for any input!</p>

<p>Congratulations on your job offers!</p>

<p>It shouldn’t negatively affect you to decline the second offer since you didn’t yet have an offer from the first company when you interviewed. On the other hand, doing well at an internship greatly increases chances of a permanent offer for after graduation.</p>

<p>Thanks for the replies. I declined the second offer, and asked them if they would be able to postpone the internship until the fall. The HR manager called me this morning and said they are going to discuss the matter, but she is confident I can do that. She is going to give me an official position next week, but my odds are good.</p>

<p>Good job. You handled the situation well.</p>