The Queensland LNP senator Ian Macdonald has apologised to his would-be successors, who he says have been “locked out” of the Senate “for a generation”, after he was given a virtually unwinnable spot on the Senate ticket.

Macdonald used his latest Northern Online Opinion dispatch to apologise for leaving the people of northern Queensland “without genuine representation in the Senate”, hinting at a succession plan he was unable to implement, after losing his battle to remain at the top of the LNP Senate ticket.

But he also made note of “under the line voting”, where constituents can direct their preferences to at least 12 individual Senate candidates, rather than an above-the-line party vote, as an opportunity to win back his seat.

“I am still on the LNP Senate ticket at the difficult No 4 position, but I will be campaigning hard and with ‘under the line’ voting now possible in the Senate, anything can happen,” he said in his dispatch.

The last time the Coalition won four Senate spots in Queensland was 2004, before the official merging of the Liberal and National parties into the LNP.

In his note to supporters, Macdonald said he was “very sorry that those several northerners, who out of deference and loyalty to me refrained from nominating from the Senate this time, have now effectively been locked out for a generation”.

“I had spoken to a number of very worthy, capable and interested people about succession when they were able to get themselves better known in [the] Brisbane/south-east Queensland region where the bulk of preselectors for the LNP reside.

“I am truly sorry that their loyalty to me has led to this situation.”

The LNP is yet to determine its Senate voting strategy.

Macdonald stridently denied to Guardian Australia he had been advised to aim for the third ticket spot, while anointing a successor for the head of the ticket.

“As with everything else reported from ‘unnamed sources’, this is a fabrication and entirely untrue,” he said.

Macdonald had nominated for each of the six LNP Senate ticket spots after it became obvious within the Queensland party he would not have the votes to retain a top ticket position.

With at least 10 of the LNP’s 21 Queensland seats having been identified by Labor as potentially winnable, locking down north Queensland has become a priority for the party.

Susan McDonald, who, in a surprise win still reverberating throughout the party, knocked off powerbroker Barry O’Sullivan for the top National party ticket spot, has announced she will move to Townsville to ensure the north maintains its Senate representation.

O’Sullivan lost by just one vote in the Senate preselection earlier this month, 121 to 120.