Haga left the conservatory after a year to study linguistics at the latter university, and she would later in her career also obtain a postgraduate degree in European policy making from the Vrije Universiteit Brussel.
[10] Haga started her career in 2001 as a clinical linguist at hospitals in Haren and Leeuwarden, and she served on the provincial board of the Dutch Association for Speech Therapy and Phoniatrics (NVLF).
[9][1] She did some trainings in business administration to switch to a corporate career in 2006, working consecutively for pharmaceutical company Wyeth and as procurement manager for medical devices producer Covidien.
Haga criticized the province's lobby when Friesland was not included in a night-time train service to the Randstad region and when it did not receive funding for the implementation of the European Rail Traffic Management System (ERTMS), which would allow for higher speeds.
[28][29] In response to abandoned plans of a railway between Heerenveen and Groningen, Haga supported an investigation into the Superbus project, a proposed high-speed vehicle that would receive a dedicated lane on the A7 motorway.
[30] In talks over the placement of wind turbines, she decried the province's slow decision making and warned that control over site selection could be taken over by the national government in the absence of a determination.
She supported the Leeuwarden food bank as vice chair and Zorgbelang Fryslân (patient interests) and World Servants Netherlands (volunteering) as supervisory board member.
[7][10] When GroenLinks broke with the governing coalition in Arnhem in October 2015, the Christian Union joined the remaining parties – D66, SP, and the CDA.
[42][45][46] Haga worked to make it easier to apply for subsidies for citizen initiatives after appropriated funds were left unused, and she selected six sites for solar farms, which would fit between 25,000 and 48,000 panels.
[47][48] Amongst an increased influx of migrants, partly as a result of the Syrian Civil War, the executive decided to postpone the closure of an emergency shelter for refugees in the Koepelgevangenis.
[49] Haga also worked with the COA [nl] to allow refugees to stay in Arnhem after receiving a residence permit, believing this would aid their integration into society.
In the municipal council, some political parties repeated complaints from neighbors of the center that no new access road was constructed, to which Haga responded that it was unnecessary from a traffic-engineering point of view.
[52][53][54] Five months after Elderhoeve's opening – when neighbors complained about nuisances and a lack of promised measures to mitigate them – Haga responded that only four reports had been filed.
[57] Opposition parties scolded Haga once more in December 2016, when she could not clearly answer whether neighbors had helped draw up evaluation criteria for the asylum seekers' center as had been promised.
[71] Haga first ran for the European Parliament in a 2019 election on the joint Christian Union – Reformed Political Party list, occupying its third spot.
[72] She presented a four-point plan for the Northern Netherlands that included protection of the Wadden Sea, better train connections to the region, stimulating circular agriculture, and advocating for preservation of Dutch Low Saxon and the West Frisian language.
[6] In a joint opinion piece, they argued the deal was just the start of necessary measures to mitigate climate change, and they said more investments and incentives would be required for the transport and agriculture sectors.
He had been asked by the Christian Union's board to make room for Haga to gain experience ahead of the 2024 European Parliament election, as Van Dalen was nearing a party-imposed term limit.
Haga told that she wanted to take care of God's creation, describing herself as a "Christian with a green heart", and she said she would focus on freedom of religion, reducing plastic usage, and a humane migration policy.
[6][78] The Christian Union's board officially announced on 12 January 2024 its nomination of Haga as lead candidate in the June 2024 European Parliament election.