* KPK probes "SN" in electronic card procurement case

* "SN" refers to Golkar chairman Setya Novanto - media

* Golkar says waiting for official notice from KPK

* Analysts say the investigation shows KPK's independence (Adds comment from Golkar official, analyst, background)

By Agustinus Beo Da Costa and Eveline Danubrata

JAKARTA, July 17 (Reuters) - Indonesia's anti-corruption agency is investigating a member of parliament for allegedly causing state losses of at least 2.3 trillion rupiah ($173 million) during the implementation of a national electronic identity card, it said on Monday.

The Corruption Eradication Commission (KPK) identified the politician only by the initials "SN", which local media took to be Setya Novanto, speaker of the House of Representatives (DPR) and chairman of Indonesia's second-biggest political party, Golkar.

KPK Chairman Agus Rahardjo said "SN" is suspected to have abused his authority to benefit himself or others while the electronic identity card, locally known as e-KTP, was put in place in 2011 and 2012.

Novanto did not respond to requests for comment.

Nurul Arifin, a spokeswoman for Golkar, said: "We are still waiting for official notice from the KPK that it had placed our chairman, Mr. Setya Novanto, as a suspect."

"The Golkar party follows and respects the process of upholding the law, and we strongly hold on to the principle of the presumption of innocence," Arifin added.

The KPK's large-scale investigation, which implicates members of President Joko Widodo's ruling party - the PDI-P - and other parties in his coalition, shows the independence of the anti-corruption agency, political analysts say.

"This most certainly demonstrates how tough the KPK is," Keith Loveard, a Jakarta-based analyst at Concord Consulting, said, adding that Widodo is unlikely to get in the way of the KPK's investigation in the e-KTP case.

"While all the parties are virtually implicated, including the PDI-P, public support for the KPK remains extremely high. So for him to attempt to slow the process or to create obstacles would be very damaging to his popularity," Loveard said.

Golkar's secretary general, Idrus Marham, said late on Monday that the party's support for Widodo's re-election bid in 2019 remains unchanged.

KPK has been investigating allegations that sums ranging from $5,000 to $5.5 million - money generated by marking up the costs of the e-KTP procurement - were divided up in a room in parliament.

In March, two public servants on trial for corruption linked to the case identified at least 37 people, including Novanto, who they said had benefited.