Comedian Stephen Colbert's surprised White House with his bid.
It is up to South Carolina Democrats to decide whether to take him seriously.
Colbert, who poses as a conservative talk show host on the Comedy Central cable network, filed to get on the ballot as a Democratic candidate in his native South Carolina. His campaign paid a $2,500 (1,733 EUR) filing fee just before the noon deadline, said state Democratic Party Chairwoman Carol Fowler.
Whether he will appear on the ballot will be decided by party officials later Thursday.
The host of "The Colbert Report" does not appear to meet the party's viable candidate qualification. And it is unclear if he would meet the requirement that candidates actively campaign in the state.
Colbert did appear Sunday at the University of South Carolina in Columbia, telling several hundred fans he would, if elected, "crush the state of Georgia." He also received a key to the capital city and the mayor declared him South Carolina's "favorite son."
When Colbert announced his candidacy on his show last month, he said he would run only in this key primary state. He said then he planned to run as a Democrat and a Republican - so he could lose twice.
The republican filing fee is $35,000 (24,267 EUR). The deadline was Thursday afternoon.