This week the US President, Mr Bush, won two major legislative victories in Washington, as the US Congress approved a major energy bill, which includes oil exploration in the Arctic, and also a patients bill of rights for medical consumers.
As they celebrated, however, Republicans were working behind the scenes to ensure that the administration's string of victories continued in the autumn, when the Senate takes up the matter of Mr Bush's controversial missile defence plan. The National Security adviser, Ms Condoleezza Rice, has spent the week on Capitol Hill meeting with senators trying to drum up support.
But Democratic Senator Joseph Biden, the influential chairman of the Senate Foreign Relations Committee, who met with Ms Rice, said yesterday he believed the Senate could defeat Mr Bush's missile defence plan if it clearly violated the 1972 Anti-Ballistic Missile Treaty and was also opposed by Europe, China and Russia.
"I'm hopeful I can convince the majority of my colleagues that it matters a great deal how the administration pursues missile defence and what it pursues," Mr Biden told the BBC.
Democrats control the Senate, and Republicans, who handed Mr Bush his wins this week, control Congress. However, Mr Biden may be prematurely optimistic if he is relying on strictly partisan support to defeat Mr Bush's plan.
Because it was three dozen Democratic Congressmen who broke ranks and handed Mr Bush his victory on the energy bill and oil-drilling plan. Some 36 Democratic Senators, including five normally staunch partisans from the Congressional Black Caucus, voted in favour of oil-drilling in the wildlife refuge. Those Democratic votes provided the margin of victory.
The reason for the party split, which may be repeated on the missile defence plan, came down to jobs. Labour unions, who normally support Democrats, argued that opening the protected Arctic wilderness to oil and gas exploration could create 700,000 new jobs. Environmental groups disputed that figure, but the issue was sufficient to fracture the usual coalition between unions and environmentalists.
"What environmentalists fail to realise is that we are not environmental organisations," a Teamster lobbyist, Mr Jerry Hood, told the New York Times. "Our responsibility is to grow the work force."
The bill, which would open up 2,000 acres along the region's coastal plain, provides $33.5 billion in tax breaks and spending incentives over 10 years to oil and power companies.
Democratic Senator John Kerry promised to try and block the bill when it arrives in the senate. "I will filibuster any effort to drill in the refuge. It will never pass the Senate."
On missile defence, a number of defence contractors will also be lobbying hard for passage of Mr Bush's proposed $8.3 billion package.
Many of those contractors are located in states represented by Democratic Senators, including California, which could put those politicians in the awkward position of cutting defence industry jobs in their districts if they do not support the Mr Bush's plan.
Nonetheless, it is clear Mr Bush will face tough negotiations with Democrats in the Senate if he hopes to persuade them to support both his energy and defence packages. But as Democrats learned this week, it would be unwise to underestimate Mr Bush.