Last night’s federal budget is more of a discussion starter than the final word when it comes to policy change in this term of government. Given the numbers in the Senate, the list of “new commitments” announced by Treasurer Joe Hockey are best interpreted as a wish-list rather than the likely end result.

It’s been around a decade since the Senate was at the heart of discussions about “what’s going to happen”, but there is no doubt that between now and Christmas the press gallery and Prime Minister Tony Abbott’s ministry will be spending a lot more time in the offices with the red carpet. Good lobbyists will as well.

To pass a bill through the Senate a government needs 39 votes, but between the Liberals and the Nationals the Coalition only has only 34 votes; after the new senators take their seats in July that number falls to 33. After July, the Labor Party will have 25, the Greens 10, the Palmer United Party holds a block of four and then there are four independents, including the wily Nick Xenophon.

Much has been made of the potential role that Clive Palmer and his senators will play in the next three years, and there is no doubt it will be a big one. But that is just the beginning of the challenges the Abbot government faces.

Put simply, the government will be able to pass any bill that the ALP or the Greens support. But, when both those parties oppose a government policy, the Coalition will need all of the Palmer block and two of the four independents. Put another way, if the ALP, Greens and Palmer all oppose a bill then it has no chance of passing.

It gets worse. Imagine if the government manages to line up Palmer and two other independents to support a bill. In such a situation every single Liberal and National senator is in the balance of power. If just one of them crossed the floor it’s back to the drawing board for the government.

Now let’s take a look at some of the government’s wish-list. They want to discourage Australians from going to the doctor so often (even though people in regional Australia go to the doctor a lot less than people in Hockey’s electorate). They want to get tough on the unemployed (even though unemployment rates are much higher in regional areas than they are in Abbott’s electorate). And they want to cut public spending on health and education (even though private schools and hospitals are few and far between in regional Australia).

The National Party has a long history of supporting legislation that hurts its constituents in exchange for a few cabinet positions and the odd ribbon-cutting ceremony for a new road. But as Palmer and Indi MP Cathy McGowan showed at the last election, Coalition MPs who vote the party line ahead of their constituents’ interests might spend less time in Parliament than they spent stacking branches.

No one knows how the Senate is going to behave, but one thing for certain is that it won’t behave in the way that suits the Abbott government. You don’t build power in the Senate by voting for the governments agenda, you build it by choosing the right bit to oppose. With 18 senators sitting on the crossbench, there will be plenty of ideas about the best things to block.