SO Tony Abbott appears to have conceded that the Coalition will have to change at least some ­aspects of its proposed $7 GP co-payment. This makes sense. There is little point in presenting legislation to the Senate, whether budget related or not, if a government cannot drum up a majority on the floor of the upper house.

In opposition, Abbott was criticised for being too negative. This overlooked the fact Abbott’s unequivocal rejection of an emissions trading scheme or carbon tax united not only the Liberal Party but also ensured the continuation of the coalition between the Liberals and Nationals. In other words, Abbott’s tactics in opposition from December 2009 made victory possible in September last year.

Yet Abbott’s alleged negativity did not affect the operation of government. In her almost three years as prime minister, Julia Gillard had an effective alliance with the Greens. In her political memoir My Story, Gillard recounted how, during her prime ministership, 566 bills passed the House of Representatives and the Senate. She reflected that “this is more legislation than was passed in the last term of the Howard government, notwithstanding their complete command of the parliament with a majority in both the House of Representatives and the Senate”.

Soon after Gillard stepped down as prime minister, commentator Gael Jennings appeared on ABC News Breakfast and declared that Gillard must be the most successful prime minister in modern Australian history.

The argument was that the more legislation the government passed, the more successful it must be. This is a familiar government-knows-best approach. Yet Jennings’s point stated the reality that the Gillard government did not have a major problem in getting a majority of its legislation through in the Senate.

Speaking on the Radio National Sunday Extra program last weekend, The Saturday Paper’s Erik Jensen suggested that the Prime Minister and his colleagues were “almost incapable of governing”. Such immature hyperbole overlooks the fact the Coalition has got much of its legislation through the upper house. This includes abolition of the carbon tax and the mining tax. This was a significant part of Abbott’s 2013 election agenda.

For the rest, there is no alternative to constant negotiations with the eight senators who represent micro-parties or who are declared independents — provided, that is, both Labor and the Greens oppose government legislation.

There is no realistic double-dissolution alternative. Robert Menzies obtained a double dissolution in 1951 essentially on the blocking of some banking legislation. This worked, partly because Labor’s ­attempt to nationalise the private trading banks had been the big domestic issue during the previous five years.

Malcolm Fraser achieved a double dissolution in early 1983. Fraser’s campaign went off-track from the start since the bills on which he had obtained the double dissolution were not issues on which he wanted to fight the ­election.

Theoretically, Abbott could have gone to an early election on the carbon tax matter. But that was the only big issue that could justify such a move.

The decision of the Palmer United Party plus Family First’s Bob Day, independent John Madigan and Liberal Democrat David Leyonhjelm to overturn the Labor-Greens carbon tax effectively removed this option. Independent Nick Xenophon was absent from the Senate vote. The Coalition needed six votes from these eight senators.

On Sky News’ Paul Murray Live recently, former Hawke government minister Graham Richardson was heard to complain about the Senate election system and wondered how it came about. Well, it’s essentially Labor’s creation. The decision that all states would have the same number of senators, irrespective of population size, was part of the Federation agreement and is reflected in the Constitution. Likewise the ­arrangement whereby the number of senators shall be half the number of the members of the House of Representatives. There is nothing anyone can realistically do about either reality, in view of the difficulty of bringing about changes to the Constitution.

This leaves the Senate election system itself. The present proportional representation system was introduced by Ben Chifley’s Labor government and came into effect at the December 1949 election. In 1949 the number of senators from each state was set at 10, with five to be elected at each half Senate election.

Under the proportional voting system that prevailed between 1949 and 1984, a Senate quota was about 17 per cent, to be achieved on a primary vote or following the allocation of preferences. In 1984, the Hawke Labor government wanted to increase the number of House of Representatives MPs. Under the nexus provisions of the Constitution, such a move required that the number of senators from each state be increased to 12; that is, six at each half Senate election. This meant that the quota dropped to about 14 per cent.

Labor’s 1984 proposal was opposed by the Liberal Party but passed with the legislative support of the Nationals. The Nationals, like Labor, thought their political fortunes would be enhanced by an increase in the number of parliamentarians in both houses of parliament. And so it came to pass that it became easier for minor parties and independents to win Senate places. A successful party under the old system could expect to win three out of five places in a half Senate election. But it is difficult to win four out of six places.

This means that a major opposition party, a minor party and independents will usually take half the Senate vacancies on offer in each state.

Moreover, the Hawke government’s decision to make it possible for electors to vote for just one party (above the line) encouraged minor parties and independents to trade preferences.

In recent years Madigan and Ricky Muir have won Senate seats on a primary vote of under 3 per cent. All the others have polled 6 per cent or above.

The Senate voting system, in existence since 1984, will be difficult to change since it would require the support of a majority of senators. But it causes problems only when the opposition and a minor party such as the Greens oppose legislation. This is a fate that Gillard was spared from most of the time. But not Abbott.