A report claims West Ham United have joined the race for Horgan, who is interesting a number of clubs including Glasgow Rangers.
Horgan, who can play on either flank, has scored 11 goals in all competitions this calendar year, but is out of contract on 31 December.
And the recent Republic of Ireland call-up could have his pick of clubs, with Sunderland last week said to be leading Newcastle United, Aston Vila and several Championship sides in the race for his signature (Telegraph).
According to the Irish Herald, Scottish giants Glasgow Rangers are also very keen on Horgan, along with Dundalk teammate Andy Boyle, although the Irish pair may find it difficult to move to Ibrox for non-footballing reasons.
West Ham currently have no shortage of wingers, however Besiktas loanee Gokhan Tore has been tipped to return to his parent club in the New Year.
Whether the Hammers will still be keen on Horgan by then remains to be seen, with the Telegraph reporting that Slaven Bilic's position as manager could be under threat.