A total of 3568 chairman aspirants, including 741 of ruling Awami League and 668 of BNP, have filed their nomination papers in 738 Union Parishads (UPs) to contest the first phase of election slated for March 22.25 chairman candidates are, however, set to be elected unopposed as their UPs got single candidates.Besides, 148 chairman hopefuls nominated by Jatiya Party submitted their nomination papers in different UPs.Though 739 UPs are going to polls on March 22, the data about the candidates of 738 were available as of Tuesday.Of the chairman aspirants, 1,900 filed the nomination papers as political party candidates, while 1,668 as independent ones.