Daly began his senior career in England, where he played for Stockport County and Hartlepool United; he also had loan spells with Bury and Grimsby Town.
[6] On 2 October 1999, Daly then made his professional football debut against Walsall and become Stockport County's second youngest player when he came off the bench, in a 2–1 win.
[27] During this season Stockport manager, Carlton Palmer, decided against naming a goalkeeper on the bench and revealed that he was planning to use Daly in net should their keeper get sent off or injured.
[28] Daly continued to form a striking partnership with Wilbraham but he struggled to score goals regularly in the first half of the season.
[32][30] On 28 February 2004, Daly returned to the starting line–up following his recall from a loan spell at Bury, in a 1–1 draw against Brighton & Hove Albion.
[43] Shortly after his loan spell at Grimsby Town came to an end and had to serve a three match suspension, he returned to the first team for Stockport County against Swansea City in the second round of the FA Cup and helped the club draw 0–0 to earn a replay.
[60] On 15 February 2005, Daly made his Hartlepool United debut, starting a match and played 74 minutes before being substituted, in a 3–2 loss against Luton Town.
[61] Since joining the club, he found himself competing in a striker position with Joel Porter, Eifion Williams and Adam Boyd.
Ahead of the 2005–06 season, Daly found himself competing for the first team place in the striker position after Hartlepool United made new signings.
[78] But his suspension was rescinded after local newspaper The Northern Echo reported that "Tyne-Tees Television supplied enhanced footage of the incident which highlighted his innocence" and he was free to play in the next match.
On 5 January 2007, Daly was allowed to join Scottish Premier League side Dundee United on a two–year contract for an undisclosed fee.
[87] After the match, Daly's performance was praised by manager Craig Levein, describing him as "tireless up front and a lot of people don't see all the work he does.
"[88] However in early May 2007, Daly suffered a posterior cruciate ligament injury, ruling him out for around six months, which saw him miss the start of the 2007–08 season.
[112] On 22 November 2009, Daly made his first appearance of the season against Celtic when he came on as a 73rd-minute substitute and scored an equalising goal, which Dundee United eventually won 2–1.
[113] After the match, manager Levein praised Daly's return, saying he was happier to be back and absolutely thrilled on the pitch after he has been out for seven or eight months and played 30 minutes of football.
[115] Since returning to the first team in late November, Daly found himself alternating between a substitute bench and starting line–up role, forming a striking partnership with Sandaza or David Goodwillie.
[119] In the final against Ross County, Daly started the whole game when he helped Dundee United win 3–0 as champions, fulfilling his target for the club as promised.
[122] Daly made his European debut and started the whole game as captain, as the club lose 1–0 against Greek side AEK Athens in the first leg of the UEFA Europa League play–off round.
[124] Daly said while his goal couldn't save the Dundee United's European campaign that could have seen the club play in the group stage, he felt their performances should have been much better.
[131] On 10 March 2011, Daly returned from injury, coming on as a 74th-minute substitute, and scored a last minute winner, in a 2–1 win against Hamilton Academical.
[134] Despite the other injury concerns that Daly faced throughout the season,[135] he continued to form a striking partnership with Goodwillie, as well as, retaining his leadership as captain.
[148] Having become a crucial part of the team and gained himself the club captaincy throughout the 2011–12 season, Daly went on to make forty–three appearances and scoring twenty–two goals in all competitions.
[154] Following his return from injury, Daly continued to form a striking partnership with Johnny Russell, as well as, retaining his leadership as Dundee United's captain.
[182] Since returning to the first team, however, he found his playing time, coming from the substitute bench and faced new competitions from the striker position, such as, Kenny Miller and Kris Boyd.
[186] Upon leaving the club, Daly was later critical of Rangers’ new chairman Dave King for "savaging out of contract players over failing to get out of the Championship".
[194] His involvement for the U19 national side saw Republic of Ireland U19 qualify for the UEFA European Under-19 Championship in Norway, including a brace against Croatia U19.
[211] On 4 November 2015, Daly agreed to join Hearts as coach of their under-20 team when his contract with Raith Rovers expired in January 2016.
[222] It was later revealed that Daly was considered for the manager but Hearts’ chairwoman Ann Budge was reluctant to choose him, citing as a "poisoned chalice".
[237] On 18 October 2024, Dundalk were relegated following a 2–0 defeat at home to Derry City, with Daly confirming after the match that he would leaving the club after their final two games of the season.
[238][239] Growing up, Daly had known Seán Dillon since they were young and "grew up together on the streets of Dublin and were team-mates at Cherry Orchard throughout their teenage years".