The remaining seat went to the Samajwadi Party in the polls marred by cross-voting from both the sides, which led to the defeat of the BSP candidate in the prestigious battle of ballots, touted as a test for the new-found bonhomie between the parties headed by Akhilesh Yadav and Mayawati.
Besides BJP's prominent winner Union Finance Minister Arun Jaitley, others who made it to the Upper House of Parliament from the party are Ashok Bajpai, Vijay Pal Singh Tomar, Sakal Deep Rajbhar, Kanta Kardam, Anil Jain, Harnath Singh Yadav, GVL Narasimha Rao and ninth candidate Anil Kumar Agarwal, who pulled off a surrpise win with the help of second preference votes.
Other candidates, including SP's actor-turned- politician Jaya Bachchan won with the help of first preference votes.
Chief Minister Yogi Adityanath told media persons that the BJP's victory in all the nine seats it contested exposed the "opportunistic face" of the SP.
"The people of the state have seen the opportunistic face of the SP. It can take votes but not give votes in return," he said, a reference to the SP's victory with the help of BSP votes in the recent Lok Sabha bypolls in Gorakhpur and Phulpur.
The chief minister said the SP's "opportunistic character" was not new and that "the people of the state have seen it over the years".
Adityanath said it was time to be careful to avoid falling into a deep pit in the future.
Railway Minister Piyush Goyal, who was BJP's central observer, said with more BJP members in the Rajya Sabha, the government would be able to ensure passage of bills in the Upper House, where the NDA does not enjoy a majority.
Counting of votes began after a two-hour delay as the opposition SP and BSP lodged a complaint with the Election Commission.
The opposition parties moved the poll panel against two MLAs who are believed to have cross-voted.
"We have given a written complaint to the EC that our MLA Anil Singh did not show his vote to the election agent of the party before casting it and we are awaiting a reply from the EC in this regard," Deputy leader of the BSP in the Assembly Uma Shankar Singh said.
The SP also lodged a similar complaint with regard to MLA Nitin Agarwal, who had switched sides after his father quit the party and joined the BJP recently.
"Nitin Agarwal cast his vote without showing it to the election agent and we have demanded the cancellation of his vote," SP MLC Sunil Singh Sajan said.
With one BSP MLA believed to have cross-voted and two others in jail being denied permission to vote in the polls, the opposition faced a challenge of numbers to ensure victory for their second candidate.
While the ruling BJP was sure of bagging eight of the 10 seats, the SP fielded Jaya Bachchan and the BSP Bhimrao Ambedkar for the remaining two seats.
As the parties totted up the numbers, BSP MLA Anil Singh indicated that he had cross-voted in favour of the BJP, saying "I am with Maharaj-ji", a reference to Uttar Pradesh Chief Minister Yogi Adityanath.
The Allahabad High Court had denied permission to BSP's Mukhtar Ansari, currently lodged in Banda jail, to vote in the polls. And a court in Firozabad had rejected a petition by SP MLA Hariom Yadav, who is in Firozabad jail.
The opposition banked heavily on the votes of two Independents -- Raghuraj Pratap Singh alias Raja Bhaiya and his close associate and MLA Vinod Saroj.
Raja Bhaiya, who has had a rocky relationship with BSP chief Mayawati, had tweeted this morning that he was with "Akhilesh ji" and specified that it did not mean that he was with the BSP.
The BSP did not take an adverse view of Raja Bhaiya's comment. "... had he had any reservations he would have said openly," said Uma Shankar Singh.
He added that he could not be sure that Anil Singh had voted for the BSP candidate.
Adding a tinge of surprise, Raja Bhaiya later met the chief minister, leaving political analysts wondering as to why he met Adityanath.
"I discussed issues pertaining to my constituency (Kunda). Every MLA has the right to discussed matters related to his or her constituency with the chief minister," he said.
Keeping it ambiguous, Anil Singh said that he had cast his vote and showed it to BSP agent Lalji Verma and the rest could be known from him.
"I have cast my vote after showing it to Lalji Verma and he will tell you the details...I am with Maharaj-ji," he said after voting at the Tilak Hall in the Assembly complex.
According to Uma Shankar Singh, 17 MLAs of the total 19 BSP legislators had cast their votes by midday and shown them to Verma. The BSP leader exuded confidence that all the nine surplus MLAs of the SP as well as seven of the Congress and one of the RLD have voted in favour of his party candidate.
"All the seven Congress MLAs went together to vote, while the SP has given us a list of their loyal MLAs," Uma Shankar Singh said.
Independent MLA Aman Mani Tripathi also said he was with "Maharaj ji" and would vote for the BJP.
There were 11 candidates for the 10 Rajya Sabha seats and 37 first preference votes were required for victory in each seat.